qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v6 0/9] target/arm: pc-relative translation blocks
@ 2022-10-06  3:38 Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 1/9] target/arm: Introduce curr_insn_len Richard Henderson
                   ` (8 more replies)
  0 siblings, 9 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm

This is the Arm specific changes required to reduce the
amount of translation for address space randomization.

Changes for v6:
  * Minor updates for patch review, r-b.


r~


Richard Henderson (9):
  target/arm: Introduce curr_insn_len
  target/arm: Change gen_goto_tb to work on displacements
  target/arm: Change gen_*set_pc_im to gen_*update_pc
  target/arm: Change gen_exception_insn* to work on displacements
  target/arm: Remove gen_exception_internal_insn pc argument
  target/arm: Change gen_jmp* to work on displacements
  target/arm: Introduce gen_pc_plus_diff for aarch64
  target/arm: Introduce gen_pc_plus_diff for aarch32
  target/arm: Enable TARGET_TB_PCREL

 target/arm/cpu-param.h        |   1 +
 target/arm/translate-a32.h    |   2 +-
 target/arm/translate.h        |  35 ++++-
 target/arm/cpu.c              |  23 ++--
 target/arm/translate-a64.c    | 174 +++++++++++++++----------
 target/arm/translate-m-nocp.c |   6 +-
 target/arm/translate-mve.c    |   2 +-
 target/arm/translate-vfp.c    |  10 +-
 target/arm/translate.c        | 235 +++++++++++++++++++++-------------
 9 files changed, 303 insertions(+), 185 deletions(-)

-- 
2.34.1



^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v6 1/9] target/arm: Introduce curr_insn_len
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 2/9] target/arm: Change gen_goto_tb to work on displacements Richard Henderson
                   ` (7 subsequent siblings)
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Philippe Mathieu-Daudé

A simple helper to retrieve the length of the current insn.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate.h     | 5 +++++
 target/arm/translate-vfp.c | 2 +-
 target/arm/translate.c     | 5 ++---
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/target/arm/translate.h b/target/arm/translate.h
index af5d4a7086..90bf7c57fc 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -226,6 +226,11 @@ static inline void disas_set_insn_syndrome(DisasContext *s, uint32_t syn)
     s->insn_start = NULL;
 }
 
+static inline int curr_insn_len(DisasContext *s)
+{
+    return s->base.pc_next - s->pc_curr;
+}
+
 /* is_jmp field values */
 #define DISAS_JUMP      DISAS_TARGET_0 /* only pc was modified dynamically */
 /* CPU state was modified dynamically; exit to main loop for interrupts. */
diff --git a/target/arm/translate-vfp.c b/target/arm/translate-vfp.c
index bd5ae27d09..94cc1e4b77 100644
--- a/target/arm/translate-vfp.c
+++ b/target/arm/translate-vfp.c
@@ -242,7 +242,7 @@ static bool vfp_access_check_a(DisasContext *s, bool ignore_vfp_enabled)
     if (s->sme_trap_nonstreaming) {
         gen_exception_insn(s, s->pc_curr, EXCP_UDEF,
                            syn_smetrap(SME_ET_Streaming,
-                                       s->base.pc_next - s->pc_curr == 2));
+                                       curr_insn_len(s) == 2));
         return false;
     }
 
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 5aaccbbf71..42e11102f7 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -6654,7 +6654,7 @@ static ISSInfo make_issinfo(DisasContext *s, int rd, bool p, bool w)
     /* ISS not valid if writeback */
     if (p && !w) {
         ret = rd;
-        if (s->base.pc_next - s->pc_curr == 2) {
+        if (curr_insn_len(s) == 2) {
             ret |= ISSIs16Bit;
         }
     } else {
@@ -9817,8 +9817,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             /* nothing more to generate */
             break;
         case DISAS_WFI:
-            gen_helper_wfi(cpu_env,
-                           tcg_constant_i32(dc->base.pc_next - dc->pc_curr));
+            gen_helper_wfi(cpu_env, tcg_constant_i32(curr_insn_len(dc)));
             /*
              * The helper doesn't necessarily throw an exception, but we
              * must go back to the main loop to check for interrupts anyway.
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 2/9] target/arm: Change gen_goto_tb to work on displacements
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 1/9] target/arm: Introduce curr_insn_len Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 3/9] target/arm: Change gen_*set_pc_im to gen_*update_pc Richard Henderson
                   ` (6 subsequent siblings)
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Peter Maydell

In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate-a64.c | 40 ++++++++++++++++++++------------------
 target/arm/translate.c     | 10 ++++++----
 2 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 78b2d91ed4..8f5c2675f7 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -378,8 +378,10 @@ static inline bool use_goto_tb(DisasContext *s, uint64_t dest)
     return translator_use_goto_tb(&s->base, dest);
 }
 
-static inline void gen_goto_tb(DisasContext *s, int n, uint64_t dest)
+static void gen_goto_tb(DisasContext *s, int n, int64_t diff)
 {
+    uint64_t dest = s->pc_curr + diff;
+
     if (use_goto_tb(s, dest)) {
         tcg_gen_goto_tb(n);
         gen_a64_set_pc_im(dest);
@@ -1362,7 +1364,7 @@ static inline AArch64DecodeFn *lookup_disas_fn(const AArch64DecodeTable *table,
  */
 static void disas_uncond_b_imm(DisasContext *s, uint32_t insn)
 {
-    uint64_t addr = s->pc_curr + sextract32(insn, 0, 26) * 4;
+    int64_t diff = sextract32(insn, 0, 26) * 4;
 
     if (insn & (1U << 31)) {
         /* BL Branch with link */
@@ -1371,7 +1373,7 @@ static void disas_uncond_b_imm(DisasContext *s, uint32_t insn)
 
     /* B Branch / BL Branch with link */
     reset_btype(s);
-    gen_goto_tb(s, 0, addr);
+    gen_goto_tb(s, 0, diff);
 }
 
 /* Compare and branch (immediate)
@@ -1383,14 +1385,14 @@ static void disas_uncond_b_imm(DisasContext *s, uint32_t insn)
 static void disas_comp_b_imm(DisasContext *s, uint32_t insn)
 {
     unsigned int sf, op, rt;
-    uint64_t addr;
+    int64_t diff;
     TCGLabel *label_match;
     TCGv_i64 tcg_cmp;
 
     sf = extract32(insn, 31, 1);
     op = extract32(insn, 24, 1); /* 0: CBZ; 1: CBNZ */
     rt = extract32(insn, 0, 5);
-    addr = s->pc_curr + sextract32(insn, 5, 19) * 4;
+    diff = sextract32(insn, 5, 19) * 4;
 
     tcg_cmp = read_cpu_reg(s, rt, sf);
     label_match = gen_new_label();
@@ -1399,9 +1401,9 @@ static void disas_comp_b_imm(DisasContext *s, uint32_t insn)
     tcg_gen_brcondi_i64(op ? TCG_COND_NE : TCG_COND_EQ,
                         tcg_cmp, 0, label_match);
 
-    gen_goto_tb(s, 0, s->base.pc_next);
+    gen_goto_tb(s, 0, 4);
     gen_set_label(label_match);
-    gen_goto_tb(s, 1, addr);
+    gen_goto_tb(s, 1, diff);
 }
 
 /* Test and branch (immediate)
@@ -1413,13 +1415,13 @@ static void disas_comp_b_imm(DisasContext *s, uint32_t insn)
 static void disas_test_b_imm(DisasContext *s, uint32_t insn)
 {
     unsigned int bit_pos, op, rt;
-    uint64_t addr;
+    int64_t diff;
     TCGLabel *label_match;
     TCGv_i64 tcg_cmp;
 
     bit_pos = (extract32(insn, 31, 1) << 5) | extract32(insn, 19, 5);
     op = extract32(insn, 24, 1); /* 0: TBZ; 1: TBNZ */
-    addr = s->pc_curr + sextract32(insn, 5, 14) * 4;
+    diff = sextract32(insn, 5, 14) * 4;
     rt = extract32(insn, 0, 5);
 
     tcg_cmp = tcg_temp_new_i64();
@@ -1430,9 +1432,9 @@ static void disas_test_b_imm(DisasContext *s, uint32_t insn)
     tcg_gen_brcondi_i64(op ? TCG_COND_NE : TCG_COND_EQ,
                         tcg_cmp, 0, label_match);
     tcg_temp_free_i64(tcg_cmp);
-    gen_goto_tb(s, 0, s->base.pc_next);
+    gen_goto_tb(s, 0, 4);
     gen_set_label(label_match);
-    gen_goto_tb(s, 1, addr);
+    gen_goto_tb(s, 1, diff);
 }
 
 /* Conditional branch (immediate)
@@ -1444,13 +1446,13 @@ static void disas_test_b_imm(DisasContext *s, uint32_t insn)
 static void disas_cond_b_imm(DisasContext *s, uint32_t insn)
 {
     unsigned int cond;
-    uint64_t addr;
+    int64_t diff;
 
     if ((insn & (1 << 4)) || (insn & (1 << 24))) {
         unallocated_encoding(s);
         return;
     }
-    addr = s->pc_curr + sextract32(insn, 5, 19) * 4;
+    diff = sextract32(insn, 5, 19) * 4;
     cond = extract32(insn, 0, 4);
 
     reset_btype(s);
@@ -1458,12 +1460,12 @@ static void disas_cond_b_imm(DisasContext *s, uint32_t insn)
         /* genuinely conditional branches */
         TCGLabel *label_match = gen_new_label();
         arm_gen_test_cc(cond, label_match);
-        gen_goto_tb(s, 0, s->base.pc_next);
+        gen_goto_tb(s, 0, 4);
         gen_set_label(label_match);
-        gen_goto_tb(s, 1, addr);
+        gen_goto_tb(s, 1, diff);
     } else {
         /* 0xe and 0xf are both "always" conditions */
-        gen_goto_tb(s, 0, addr);
+        gen_goto_tb(s, 0, diff);
     }
 }
 
@@ -1637,7 +1639,7 @@ static void handle_sync(DisasContext *s, uint32_t insn,
          * any pending interrupts immediately.
          */
         reset_btype(s);
-        gen_goto_tb(s, 0, s->base.pc_next);
+        gen_goto_tb(s, 0, 4);
         return;
 
     case 7: /* SB */
@@ -1649,7 +1651,7 @@ static void handle_sync(DisasContext *s, uint32_t insn,
          * MB and end the TB instead.
          */
         tcg_gen_mb(TCG_MO_ALL | TCG_BAR_SC);
-        gen_goto_tb(s, 0, s->base.pc_next);
+        gen_goto_tb(s, 0, 4);
         return;
 
     default:
@@ -14955,7 +14957,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         switch (dc->base.is_jmp) {
         case DISAS_NEXT:
         case DISAS_TOO_MANY:
-            gen_goto_tb(dc, 1, dc->base.pc_next);
+            gen_goto_tb(dc, 1, 4);
             break;
         default:
         case DISAS_UPDATE_EXIT:
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 42e11102f7..6855128fb1 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -2594,8 +2594,10 @@ static void gen_goto_ptr(void)
  * cpu_loop_exec. Any live exit_requests will be processed as we
  * enter the next TB.
  */
-static void gen_goto_tb(DisasContext *s, int n, target_ulong dest)
+static void gen_goto_tb(DisasContext *s, int n, int diff)
 {
+    target_ulong dest = s->pc_curr + diff;
+
     if (translator_use_goto_tb(&s->base, dest)) {
         tcg_gen_goto_tb(n);
         gen_set_pc_im(s, dest);
@@ -2629,7 +2631,7 @@ static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
          *    gen_jmp();
          * on the second call to gen_jmp().
          */
-        gen_goto_tb(s, tbno, dest);
+        gen_goto_tb(s, tbno, dest - s->pc_curr);
         break;
     case DISAS_UPDATE_NOCHAIN:
     case DISAS_UPDATE_EXIT:
@@ -9798,7 +9800,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         switch (dc->base.is_jmp) {
         case DISAS_NEXT:
         case DISAS_TOO_MANY:
-            gen_goto_tb(dc, 1, dc->base.pc_next);
+            gen_goto_tb(dc, 1, curr_insn_len(dc));
             break;
         case DISAS_UPDATE_NOCHAIN:
             gen_set_pc_im(dc, dc->base.pc_next);
@@ -9850,7 +9852,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             gen_set_pc_im(dc, dc->base.pc_next);
             gen_singlestep_exception(dc);
         } else {
-            gen_goto_tb(dc, 1, dc->base.pc_next);
+            gen_goto_tb(dc, 1, curr_insn_len(dc));
         }
     }
 }
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 3/9] target/arm: Change gen_*set_pc_im to gen_*update_pc
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 1/9] target/arm: Introduce curr_insn_len Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 2/9] target/arm: Change gen_goto_tb to work on displacements Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 4/9] target/arm: Change gen_exception_insn* to work on displacements Richard Henderson
                   ` (5 subsequent siblings)
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Philippe Mathieu-Daudé

In preparation for TARGET_TB_PCREL, reduce reliance on
absolute values by passing in pc difference.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate-a32.h |  2 +-
 target/arm/translate.h     |  6 ++--
 target/arm/translate-a64.c | 32 +++++++++---------
 target/arm/translate-vfp.c |  2 +-
 target/arm/translate.c     | 68 ++++++++++++++++++++------------------
 5 files changed, 56 insertions(+), 54 deletions(-)

diff --git a/target/arm/translate-a32.h b/target/arm/translate-a32.h
index 78a84c1414..5339c22f1e 100644
--- a/target/arm/translate-a32.h
+++ b/target/arm/translate-a32.h
@@ -40,7 +40,7 @@ void write_neon_element64(TCGv_i64 src, int reg, int ele, MemOp memop);
 TCGv_i32 add_reg_for_lit(DisasContext *s, int reg, int ofs);
 void gen_set_cpsr(TCGv_i32 var, uint32_t mask);
 void gen_set_condexec(DisasContext *s);
-void gen_set_pc_im(DisasContext *s, target_ulong val);
+void gen_update_pc(DisasContext *s, target_long diff);
 void gen_lookup_tb(DisasContext *s);
 long vfp_reg_offset(bool dp, unsigned reg);
 long neon_full_reg_offset(unsigned reg);
diff --git a/target/arm/translate.h b/target/arm/translate.h
index 90bf7c57fc..d651044855 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -254,7 +254,7 @@ static inline int curr_insn_len(DisasContext *s)
  * For instructions which want an immediate exit to the main loop, as opposed
  * to attempting to use lookup_and_goto_ptr.  Unlike DISAS_UPDATE_EXIT, this
  * doesn't write the PC on exiting the translation loop so you need to ensure
- * something (gen_a64_set_pc_im or runtime helper) has done so before we reach
+ * something (gen_a64_update_pc or runtime helper) has done so before we reach
  * return from cpu_tb_exec.
  */
 #define DISAS_EXIT      DISAS_TARGET_9
@@ -263,14 +263,14 @@ static inline int curr_insn_len(DisasContext *s)
 
 #ifdef TARGET_AARCH64
 void a64_translate_init(void);
-void gen_a64_set_pc_im(uint64_t val);
+void gen_a64_update_pc(DisasContext *s, target_long diff);
 extern const TranslatorOps aarch64_translator_ops;
 #else
 static inline void a64_translate_init(void)
 {
 }
 
-static inline void gen_a64_set_pc_im(uint64_t val)
+static inline void gen_a64_update_pc(DisasContext *s, target_long diff)
 {
 }
 #endif
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 8f5c2675f7..914c789187 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -148,9 +148,9 @@ static void reset_btype(DisasContext *s)
     }
 }
 
-void gen_a64_set_pc_im(uint64_t val)
+void gen_a64_update_pc(DisasContext *s, target_long diff)
 {
-    tcg_gen_movi_i64(cpu_pc, val);
+    tcg_gen_movi_i64(cpu_pc, s->pc_curr + diff);
 }
 
 /*
@@ -342,14 +342,14 @@ static void gen_exception_internal(int excp)
 
 static void gen_exception_internal_insn(DisasContext *s, uint64_t pc, int excp)
 {
-    gen_a64_set_pc_im(pc);
+    gen_a64_update_pc(s, pc - s->pc_curr);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
 }
 
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syndrome)
 {
-    gen_a64_set_pc_im(s->pc_curr);
+    gen_a64_update_pc(s, 0);
     gen_helper_exception_bkpt_insn(cpu_env, tcg_constant_i32(syndrome));
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -384,11 +384,11 @@ static void gen_goto_tb(DisasContext *s, int n, int64_t diff)
 
     if (use_goto_tb(s, dest)) {
         tcg_gen_goto_tb(n);
-        gen_a64_set_pc_im(dest);
+        gen_a64_update_pc(s, diff);
         tcg_gen_exit_tb(s->base.tb, n);
         s->base.is_jmp = DISAS_NORETURN;
     } else {
-        gen_a64_set_pc_im(dest);
+        gen_a64_update_pc(s, diff);
         if (s->ss_active) {
             gen_step_complete_exception(s);
         } else {
@@ -1960,7 +1960,7 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread,
         uint32_t syndrome;
 
         syndrome = syn_aa64_sysregtrap(op0, op1, op2, crn, crm, rt, isread);
-        gen_a64_set_pc_im(s->pc_curr);
+        gen_a64_update_pc(s, 0);
         gen_helper_access_check_cp_reg(cpu_env,
                                        tcg_constant_ptr(ri),
                                        tcg_constant_i32(syndrome),
@@ -1970,7 +1970,7 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread,
          * The readfn or writefn might raise an exception;
          * synchronize the CPU state in case it does.
          */
-        gen_a64_set_pc_im(s->pc_curr);
+        gen_a64_update_pc(s, 0);
     }
 
     /* Handle special cases first */
@@ -2180,7 +2180,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
             /* The pre HVC helper handles cases when HVC gets trapped
              * as an undefined insn by runtime configuration.
              */
-            gen_a64_set_pc_im(s->pc_curr);
+            gen_a64_update_pc(s, 0);
             gen_helper_pre_hvc(cpu_env);
             gen_ss_advance(s);
             gen_exception_insn_el(s, s->base.pc_next, EXCP_HVC,
@@ -2191,7 +2191,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
                 unallocated_encoding(s);
                 break;
             }
-            gen_a64_set_pc_im(s->pc_curr);
+            gen_a64_update_pc(s, 0);
             gen_helper_pre_smc(cpu_env, tcg_constant_i32(syn_aa64_smc(imm16)));
             gen_ss_advance(s);
             gen_exception_insn_el(s, s->base.pc_next, EXCP_SMC,
@@ -14944,7 +14944,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
          */
         switch (dc->base.is_jmp) {
         default:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             /* fall through */
         case DISAS_EXIT:
         case DISAS_JUMP:
@@ -14961,13 +14961,13 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             break;
         default:
         case DISAS_UPDATE_EXIT:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             /* fall through */
         case DISAS_EXIT:
             tcg_gen_exit_tb(NULL, 0);
             break;
         case DISAS_UPDATE_NOCHAIN:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             /* fall through */
         case DISAS_JUMP:
             tcg_gen_lookup_and_goto_ptr();
@@ -14976,11 +14976,11 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         case DISAS_SWI:
             break;
         case DISAS_WFE:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             gen_helper_wfe(cpu_env);
             break;
         case DISAS_YIELD:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             gen_helper_yield(cpu_env);
             break;
         case DISAS_WFI:
@@ -14988,7 +14988,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
              * This is a special case because we don't want to just halt
              * the CPU if trying to debug across a WFI.
              */
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             gen_helper_wfi(cpu_env, tcg_constant_i32(4));
             /*
              * The helper doesn't necessarily throw an exception, but we
diff --git a/target/arm/translate-vfp.c b/target/arm/translate-vfp.c
index 94cc1e4b77..070f465b17 100644
--- a/target/arm/translate-vfp.c
+++ b/target/arm/translate-vfp.c
@@ -856,7 +856,7 @@ static bool trans_VMSR_VMRS(DisasContext *s, arg_VMSR_VMRS *a)
         case ARM_VFP_FPSID:
             if (s->current_el == 1) {
                 gen_set_condexec(s);
-                gen_set_pc_im(s, s->pc_curr);
+                gen_update_pc(s, 0);
                 gen_helper_check_hcr_el2_trap(cpu_env,
                                               tcg_constant_i32(a->rt),
                                               tcg_constant_i32(a->reg));
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 6855128fb1..01b7536c7e 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -772,9 +772,9 @@ void gen_set_condexec(DisasContext *s)
     }
 }
 
-void gen_set_pc_im(DisasContext *s, target_ulong val)
+void gen_update_pc(DisasContext *s, target_long diff)
 {
-    tcg_gen_movi_i32(cpu_R[15], val);
+    tcg_gen_movi_i32(cpu_R[15], s->pc_curr + diff);
 }
 
 /* Set PC and Thumb state from var.  var is marked as dead.  */
@@ -866,7 +866,7 @@ static inline void gen_bxns(DisasContext *s, int rm)
 
     /* The bxns helper may raise an EXCEPTION_EXIT exception, so in theory
      * we need to sync state before calling it, but:
-     *  - we don't need to do gen_set_pc_im() because the bxns helper will
+     *  - we don't need to do gen_update_pc() because the bxns helper will
      *    always set the PC itself
      *  - we don't need to do gen_set_condexec() because BXNS is UNPREDICTABLE
      *    unless it's outside an IT block or the last insn in an IT block,
@@ -887,7 +887,7 @@ static inline void gen_blxns(DisasContext *s, int rm)
      * We do however need to set the PC, because the blxns helper reads it.
      * The blxns helper may throw an exception.
      */
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     gen_helper_v7m_blxns(cpu_env, var);
     tcg_temp_free_i32(var);
     s->base.is_jmp = DISAS_EXIT;
@@ -1055,7 +1055,7 @@ static inline void gen_hvc(DisasContext *s, int imm16)
      * as an undefined insn by runtime configuration (ie before
      * the insn really executes).
      */
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_pre_hvc(cpu_env);
     /* Otherwise we will treat this as a real exception which
      * happens after execution of the insn. (The distinction matters
@@ -1063,7 +1063,7 @@ static inline void gen_hvc(DisasContext *s, int imm16)
      * for single stepping.)
      */
     s->svc_imm = imm16;
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     s->base.is_jmp = DISAS_HVC;
 }
 
@@ -1072,16 +1072,16 @@ static inline void gen_smc(DisasContext *s)
     /* As with HVC, we may take an exception either before or after
      * the insn executes.
      */
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_pre_smc(cpu_env, tcg_constant_i32(syn_aa32_smc()));
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     s->base.is_jmp = DISAS_SMC;
 }
 
 static void gen_exception_internal_insn(DisasContext *s, uint32_t pc, int excp)
 {
     gen_set_condexec(s);
-    gen_set_pc_im(s, pc);
+    gen_update_pc(s, pc - s->pc_curr);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -1107,10 +1107,10 @@ static void gen_exception_insn_el_v(DisasContext *s, uint64_t pc, int excp,
                                     uint32_t syn, TCGv_i32 tcg_el)
 {
     if (s->aarch64) {
-        gen_a64_set_pc_im(pc);
+        gen_a64_update_pc(s, pc - s->pc_curr);
     } else {
         gen_set_condexec(s);
-        gen_set_pc_im(s, pc);
+        gen_update_pc(s, pc - s->pc_curr);
     }
     gen_exception_el_v(excp, syn, tcg_el);
     s->base.is_jmp = DISAS_NORETURN;
@@ -1125,10 +1125,10 @@ void gen_exception_insn_el(DisasContext *s, uint64_t pc, int excp,
 void gen_exception_insn(DisasContext *s, uint64_t pc, int excp, uint32_t syn)
 {
     if (s->aarch64) {
-        gen_a64_set_pc_im(pc);
+        gen_a64_update_pc(s, pc - s->pc_curr);
     } else {
         gen_set_condexec(s);
-        gen_set_pc_im(s, pc);
+        gen_update_pc(s, pc - s->pc_curr);
     }
     gen_exception(excp, syn);
     s->base.is_jmp = DISAS_NORETURN;
@@ -1137,7 +1137,7 @@ void gen_exception_insn(DisasContext *s, uint64_t pc, int excp, uint32_t syn)
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syn)
 {
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_exception_bkpt_insn(cpu_env, tcg_constant_i32(syn));
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -2600,10 +2600,10 @@ static void gen_goto_tb(DisasContext *s, int n, int diff)
 
     if (translator_use_goto_tb(&s->base, dest)) {
         tcg_gen_goto_tb(n);
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         tcg_gen_exit_tb(s->base.tb, n);
     } else {
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         gen_goto_ptr();
     }
     s->base.is_jmp = DISAS_NORETURN;
@@ -2612,9 +2612,11 @@ static void gen_goto_tb(DisasContext *s, int n, int diff)
 /* Jump, specifying which TB number to use if we gen_goto_tb() */
 static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
 {
+    int diff = dest - s->pc_curr;
+
     if (unlikely(s->ss_active)) {
         /* An indirect jump so that we still trigger the debug exception.  */
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         s->base.is_jmp = DISAS_JUMP;
         return;
     }
@@ -2631,7 +2633,7 @@ static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
          *    gen_jmp();
          * on the second call to gen_jmp().
          */
-        gen_goto_tb(s, tbno, dest - s->pc_curr);
+        gen_goto_tb(s, tbno, diff);
         break;
     case DISAS_UPDATE_NOCHAIN:
     case DISAS_UPDATE_EXIT:
@@ -2640,7 +2642,7 @@ static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
          * Avoid using goto_tb so we really do exit back to the main loop
          * and don't chain to another TB.
          */
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         gen_goto_ptr();
         s->base.is_jmp = DISAS_NORETURN;
         break;
@@ -2908,7 +2910,7 @@ static void gen_msr_banked(DisasContext *s, int r, int sysm, int rn)
 
     /* Sync state because msr_banked() can raise exceptions */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     tcg_reg = load_reg(s, rn);
     gen_helper_msr_banked(cpu_env, tcg_reg,
                           tcg_constant_i32(tgtmode),
@@ -2928,7 +2930,7 @@ static void gen_mrs_banked(DisasContext *s, int r, int sysm, int rn)
 
     /* Sync state because mrs_banked() can raise exceptions */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     tcg_reg = tcg_temp_new_i32();
     gen_helper_mrs_banked(tcg_reg, cpu_env,
                           tcg_constant_i32(tgtmode),
@@ -4749,7 +4751,7 @@ static void do_coproc_insn(DisasContext *s, int cpnum, int is64,
             }
 
             gen_set_condexec(s);
-            gen_set_pc_im(s, s->pc_curr);
+            gen_update_pc(s, 0);
             gen_helper_access_check_cp_reg(cpu_env,
                                            tcg_constant_ptr(ri),
                                            tcg_constant_i32(syndrome),
@@ -4760,7 +4762,7 @@ static void do_coproc_insn(DisasContext *s, int cpnum, int is64,
              * synchronize the CPU state in case it does.
              */
             gen_set_condexec(s);
-            gen_set_pc_im(s, s->pc_curr);
+            gen_update_pc(s, 0);
         }
 
         /* Handle special cases first */
@@ -4774,7 +4776,7 @@ static void do_coproc_insn(DisasContext *s, int cpnum, int is64,
                 unallocated_encoding(s);
                 return;
             }
-            gen_set_pc_im(s, s->base.pc_next);
+            gen_update_pc(s, curr_insn_len(s));
             s->base.is_jmp = DISAS_WFI;
             return;
         default:
@@ -5161,7 +5163,7 @@ static void gen_srs(DisasContext *s,
     addr = tcg_temp_new_i32();
     /* get_r13_banked() will raise an exception if called from System mode */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_get_r13_banked(addr, cpu_env, tcg_constant_i32(mode));
     switch (amode) {
     case 0: /* DA */
@@ -6230,7 +6232,7 @@ static bool trans_YIELD(DisasContext *s, arg_YIELD *a)
      * scheduling of other vCPUs.
      */
     if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
-        gen_set_pc_im(s, s->base.pc_next);
+        gen_update_pc(s, curr_insn_len(s));
         s->base.is_jmp = DISAS_YIELD;
     }
     return true;
@@ -6246,7 +6248,7 @@ static bool trans_WFE(DisasContext *s, arg_WFE *a)
      * implemented so we can't sleep like WFI does.
      */
     if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
-        gen_set_pc_im(s, s->base.pc_next);
+        gen_update_pc(s, curr_insn_len(s));
         s->base.is_jmp = DISAS_WFE;
     }
     return true;
@@ -6255,7 +6257,7 @@ static bool trans_WFE(DisasContext *s, arg_WFE *a)
 static bool trans_WFI(DisasContext *s, arg_WFI *a)
 {
     /* For WFI, halt the vCPU until an IRQ. */
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     s->base.is_jmp = DISAS_WFI;
     return true;
 }
@@ -8765,7 +8767,7 @@ static bool trans_SVC(DisasContext *s, arg_SVC *a)
         (a->imm == semihost_imm)) {
         gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST);
     } else {
-        gen_set_pc_im(s, s->base.pc_next);
+        gen_update_pc(s, curr_insn_len(s));
         s->svc_imm = a->imm;
         s->base.is_jmp = DISAS_SWI;
     }
@@ -9779,7 +9781,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         case DISAS_TOO_MANY:
         case DISAS_UPDATE_EXIT:
         case DISAS_UPDATE_NOCHAIN:
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             /* fall through */
         default:
             /* FIXME: Single stepping a WFI insn will not halt the CPU. */
@@ -9803,13 +9805,13 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             gen_goto_tb(dc, 1, curr_insn_len(dc));
             break;
         case DISAS_UPDATE_NOCHAIN:
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             /* fall through */
         case DISAS_JUMP:
             gen_goto_ptr();
             break;
         case DISAS_UPDATE_EXIT:
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             /* fall through */
         default:
             /* indicate that the hash table must be used to find the next TB */
@@ -9849,7 +9851,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         gen_set_label(dc->condlabel);
         gen_set_condexec(dc);
         if (unlikely(dc->ss_active)) {
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             gen_singlestep_exception(dc);
         } else {
             gen_goto_tb(dc, 1, curr_insn_len(dc));
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 4/9] target/arm: Change gen_exception_insn* to work on displacements
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
                   ` (2 preceding siblings ...)
  2022-10-06  3:38 ` [PATCH v6 3/9] target/arm: Change gen_*set_pc_im to gen_*update_pc Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 5/9] target/arm: Remove gen_exception_internal_insn pc argument Richard Henderson
                   ` (4 subsequent siblings)
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Philippe Mathieu-Daudé

In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate.h        |  5 +++--
 target/arm/translate-a64.c    | 28 ++++++++++-------------
 target/arm/translate-m-nocp.c |  6 ++---
 target/arm/translate-mve.c    |  2 +-
 target/arm/translate-vfp.c    |  6 ++---
 target/arm/translate.c        | 42 +++++++++++++++++------------------
 6 files changed, 43 insertions(+), 46 deletions(-)

diff --git a/target/arm/translate.h b/target/arm/translate.h
index d651044855..4aa239e23c 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -281,9 +281,10 @@ void arm_jump_cc(DisasCompare *cmp, TCGLabel *label);
 void arm_gen_test_cc(int cc, TCGLabel *label);
 MemOp pow2_align(unsigned i);
 void unallocated_encoding(DisasContext *s);
-void gen_exception_insn_el(DisasContext *s, uint64_t pc, int excp,
+void gen_exception_insn_el(DisasContext *s, target_long pc_diff, int excp,
                            uint32_t syn, uint32_t target_el);
-void gen_exception_insn(DisasContext *s, uint64_t pc, int excp, uint32_t syn);
+void gen_exception_insn(DisasContext *s, target_long pc_diff,
+                        int excp, uint32_t syn);
 
 /* Return state of Alternate Half-precision flag, caller frees result */
 static inline TCGv_i32 get_ahp_flag(void)
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 914c789187..2621b3b36a 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1163,7 +1163,7 @@ static bool fp_access_check_only(DisasContext *s)
         assert(!s->fp_access_checked);
         s->fp_access_checked = true;
 
-        gen_exception_insn_el(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn_el(s, 0, EXCP_UDEF,
                               syn_fp_access_trap(1, 0xe, false, 0),
                               s->fp_excp_el);
         return false;
@@ -1178,7 +1178,7 @@ static bool fp_access_check(DisasContext *s)
         return false;
     }
     if (s->sme_trap_nonstreaming && s->is_nonstreaming) {
-        gen_exception_insn(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn(s, 0, EXCP_UDEF,
                            syn_smetrap(SME_ET_Streaming, false));
         return false;
     }
@@ -1198,7 +1198,7 @@ bool sve_access_check(DisasContext *s)
             goto fail_exit;
         }
     } else if (s->sve_excp_el) {
-        gen_exception_insn_el(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn_el(s, 0, EXCP_UDEF,
                               syn_sve_access_trap(), s->sve_excp_el);
         goto fail_exit;
     }
@@ -1220,7 +1220,7 @@ bool sve_access_check(DisasContext *s)
 static bool sme_access_check(DisasContext *s)
 {
     if (s->sme_excp_el) {
-        gen_exception_insn_el(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn_el(s, 0, EXCP_UDEF,
                               syn_smetrap(SME_ET_AccessTrap, false),
                               s->sme_excp_el);
         return false;
@@ -1250,12 +1250,12 @@ bool sme_enabled_check_with_svcr(DisasContext *s, unsigned req)
         return false;
     }
     if (FIELD_EX64(req, SVCR, SM) && !s->pstate_sm) {
-        gen_exception_insn(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn(s, 0, EXCP_UDEF,
                            syn_smetrap(SME_ET_NotStreaming, false));
         return false;
     }
     if (FIELD_EX64(req, SVCR, ZA) && !s->pstate_za) {
-        gen_exception_insn(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn(s, 0, EXCP_UDEF,
                            syn_smetrap(SME_ET_InactiveZA, false));
         return false;
     }
@@ -1915,7 +1915,7 @@ static void gen_sysreg_undef(DisasContext *s, bool isread,
     } else {
         syndrome = syn_uncategorized();
     }
-    gen_exception_insn(s, s->pc_curr, EXCP_UDEF, syndrome);
+    gen_exception_insn(s, 0, EXCP_UDEF, syndrome);
 }
 
 /* MRS - move from system register
@@ -2169,8 +2169,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
         switch (op2_ll) {
         case 1:                                                     /* SVC */
             gen_ss_advance(s);
-            gen_exception_insn(s, s->base.pc_next, EXCP_SWI,
-                               syn_aa64_svc(imm16));
+            gen_exception_insn(s, 4, EXCP_SWI, syn_aa64_svc(imm16));
             break;
         case 2:                                                     /* HVC */
             if (s->current_el == 0) {
@@ -2183,8 +2182,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
             gen_a64_update_pc(s, 0);
             gen_helper_pre_hvc(cpu_env);
             gen_ss_advance(s);
-            gen_exception_insn_el(s, s->base.pc_next, EXCP_HVC,
-                                  syn_aa64_hvc(imm16), 2);
+            gen_exception_insn_el(s, 4, EXCP_HVC, syn_aa64_hvc(imm16), 2);
             break;
         case 3:                                                     /* SMC */
             if (s->current_el == 0) {
@@ -2194,8 +2192,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
             gen_a64_update_pc(s, 0);
             gen_helper_pre_smc(cpu_env, tcg_constant_i32(syn_aa64_smc(imm16)));
             gen_ss_advance(s);
-            gen_exception_insn_el(s, s->base.pc_next, EXCP_SMC,
-                                  syn_aa64_smc(imm16), 3);
+            gen_exception_insn_el(s, 4, EXCP_SMC, syn_aa64_smc(imm16), 3);
             break;
         default:
             unallocated_encoding(s);
@@ -14833,7 +14830,7 @@ static void aarch64_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
          * Illegal execution state. This has priority over BTI
          * exceptions, but comes after instruction abort exceptions.
          */
-        gen_exception_insn(s, s->pc_curr, EXCP_UDEF, syn_illegalstate());
+        gen_exception_insn(s, 0, EXCP_UDEF, syn_illegalstate());
         return;
     }
 
@@ -14864,8 +14861,7 @@ static void aarch64_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
             if (s->btype != 0
                 && s->guarded_page
                 && !btype_destination_ok(insn, s->bt, s->btype)) {
-                gen_exception_insn(s, s->pc_curr, EXCP_UDEF,
-                                   syn_btitrap(s->btype));
+                gen_exception_insn(s, 0, EXCP_UDEF, syn_btitrap(s->btype));
                 return;
             }
         } else {
diff --git a/target/arm/translate-m-nocp.c b/target/arm/translate-m-nocp.c
index 4029d7fdd4..694fae7e2e 100644
--- a/target/arm/translate-m-nocp.c
+++ b/target/arm/translate-m-nocp.c
@@ -143,7 +143,7 @@ static bool trans_VSCCLRM(DisasContext *s, arg_VSCCLRM *a)
     tcg_gen_brcondi_i32(TCG_COND_EQ, sfpa, 0, s->condlabel);
 
     if (s->fp_excp_el != 0) {
-        gen_exception_insn_el(s, s->pc_curr, EXCP_NOCP,
+        gen_exception_insn_el(s, 0, EXCP_NOCP,
                               syn_uncategorized(), s->fp_excp_el);
         return true;
     }
@@ -765,12 +765,12 @@ static bool trans_NOCP(DisasContext *s, arg_nocp *a)
     }
 
     if (a->cp != 10) {
-        gen_exception_insn(s, s->pc_curr, EXCP_NOCP, syn_uncategorized());
+        gen_exception_insn(s, 0, EXCP_NOCP, syn_uncategorized());
         return true;
     }
 
     if (s->fp_excp_el != 0) {
-        gen_exception_insn_el(s, s->pc_curr, EXCP_NOCP,
+        gen_exception_insn_el(s, 0, EXCP_NOCP,
                               syn_uncategorized(), s->fp_excp_el);
         return true;
     }
diff --git a/target/arm/translate-mve.c b/target/arm/translate-mve.c
index 0cf1b5ea4f..db7ea3f603 100644
--- a/target/arm/translate-mve.c
+++ b/target/arm/translate-mve.c
@@ -100,7 +100,7 @@ bool mve_eci_check(DisasContext *s)
         return true;
     default:
         /* Reserved value: INVSTATE UsageFault */
-        gen_exception_insn(s, s->pc_curr, EXCP_INVSTATE, syn_uncategorized());
+        gen_exception_insn(s, 0, EXCP_INVSTATE, syn_uncategorized());
         return false;
     }
 }
diff --git a/target/arm/translate-vfp.c b/target/arm/translate-vfp.c
index 070f465b17..5c5d58d2c6 100644
--- a/target/arm/translate-vfp.c
+++ b/target/arm/translate-vfp.c
@@ -230,7 +230,7 @@ static bool vfp_access_check_a(DisasContext *s, bool ignore_vfp_enabled)
         int coproc = arm_dc_feature(s, ARM_FEATURE_V8) ? 0 : 0xa;
         uint32_t syn = syn_fp_access_trap(1, 0xe, false, coproc);
 
-        gen_exception_insn_el(s, s->pc_curr, EXCP_UDEF, syn, s->fp_excp_el);
+        gen_exception_insn_el(s, 0, EXCP_UDEF, syn, s->fp_excp_el);
         return false;
     }
 
@@ -240,7 +240,7 @@ static bool vfp_access_check_a(DisasContext *s, bool ignore_vfp_enabled)
      * appear to be any insns which touch VFP which are allowed.
      */
     if (s->sme_trap_nonstreaming) {
-        gen_exception_insn(s, s->pc_curr, EXCP_UDEF,
+        gen_exception_insn(s, 0, EXCP_UDEF,
                            syn_smetrap(SME_ET_Streaming,
                                        curr_insn_len(s) == 2));
         return false;
@@ -272,7 +272,7 @@ bool vfp_access_check_m(DisasContext *s, bool skip_context_update)
          * the encoding space handled by the patterns in m-nocp.decode,
          * and for them we may need to raise NOCP here.
          */
-        gen_exception_insn_el(s, s->pc_curr, EXCP_NOCP,
+        gen_exception_insn_el(s, 0, EXCP_NOCP,
                               syn_uncategorized(), s->fp_excp_el);
         return false;
     }
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 01b7536c7e..f9d3128656 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -1103,32 +1103,34 @@ static void gen_exception(int excp, uint32_t syndrome)
                                        tcg_constant_i32(syndrome));
 }
 
-static void gen_exception_insn_el_v(DisasContext *s, uint64_t pc, int excp,
-                                    uint32_t syn, TCGv_i32 tcg_el)
+static void gen_exception_insn_el_v(DisasContext *s, target_long pc_diff,
+                                    int excp, uint32_t syn, TCGv_i32 tcg_el)
 {
     if (s->aarch64) {
-        gen_a64_update_pc(s, pc - s->pc_curr);
+        gen_a64_update_pc(s, pc_diff);
     } else {
         gen_set_condexec(s);
-        gen_update_pc(s, pc - s->pc_curr);
+        gen_update_pc(s, pc_diff);
     }
     gen_exception_el_v(excp, syn, tcg_el);
     s->base.is_jmp = DISAS_NORETURN;
 }
 
-void gen_exception_insn_el(DisasContext *s, uint64_t pc, int excp,
+void gen_exception_insn_el(DisasContext *s, target_long pc_diff, int excp,
                            uint32_t syn, uint32_t target_el)
 {
-    gen_exception_insn_el_v(s, pc, excp, syn, tcg_constant_i32(target_el));
+    gen_exception_insn_el_v(s, pc_diff, excp, syn,
+                            tcg_constant_i32(target_el));
 }
 
-void gen_exception_insn(DisasContext *s, uint64_t pc, int excp, uint32_t syn)
+void gen_exception_insn(DisasContext *s, target_long pc_diff,
+                        int excp, uint32_t syn)
 {
     if (s->aarch64) {
-        gen_a64_update_pc(s, pc - s->pc_curr);
+        gen_a64_update_pc(s, pc_diff);
     } else {
         gen_set_condexec(s);
-        gen_update_pc(s, pc - s->pc_curr);
+        gen_update_pc(s, pc_diff);
     }
     gen_exception(excp, syn);
     s->base.is_jmp = DISAS_NORETURN;
@@ -1145,7 +1147,7 @@ static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syn)
 void unallocated_encoding(DisasContext *s)
 {
     /* Unallocated and reserved encodings are uncategorized */
-    gen_exception_insn(s, s->pc_curr, EXCP_UDEF, syn_uncategorized());
+    gen_exception_insn(s, 0, EXCP_UDEF, syn_uncategorized());
 }
 
 /* Force a TB lookup after an instruction that changes the CPU state.  */
@@ -2869,7 +2871,7 @@ static bool msr_banked_access_decode(DisasContext *s, int r, int sysm, int rn,
                 tcg_el = tcg_constant_i32(3);
             }
 
-            gen_exception_insn_el_v(s, s->pc_curr, EXCP_UDEF,
+            gen_exception_insn_el_v(s, 0, EXCP_UDEF,
                                     syn_uncategorized(), tcg_el);
             tcg_temp_free_i32(tcg_el);
             return false;
@@ -2895,7 +2897,7 @@ static bool msr_banked_access_decode(DisasContext *s, int r, int sysm, int rn,
 
 undef:
     /* If we get here then some access check did not pass */
-    gen_exception_insn(s, s->pc_curr, EXCP_UDEF, syn_uncategorized());
+    gen_exception_insn(s, 0, EXCP_UDEF, syn_uncategorized());
     return false;
 }
 
@@ -5119,8 +5121,7 @@ static void gen_srs(DisasContext *s,
      * For the UNPREDICTABLE cases we choose to UNDEF.
      */
     if (s->current_el == 1 && !s->ns && mode == ARM_CPU_MODE_MON) {
-        gen_exception_insn_el(s, s->pc_curr, EXCP_UDEF,
-                              syn_uncategorized(), 3);
+        gen_exception_insn_el(s, 0, EXCP_UDEF, syn_uncategorized(), 3);
         return;
     }
 
@@ -8502,7 +8503,7 @@ static bool trans_WLS(DisasContext *s, arg_WLS *a)
          * Do the check-and-raise-exception by hand.
          */
         if (s->fp_excp_el) {
-            gen_exception_insn_el(s, s->pc_curr, EXCP_NOCP,
+            gen_exception_insn_el(s, 0, EXCP_NOCP,
                                   syn_uncategorized(), s->fp_excp_el);
             return true;
         }
@@ -8605,7 +8606,7 @@ static bool trans_LE(DisasContext *s, arg_LE *a)
         tmp = load_cpu_field(v7m.ltpsize);
         tcg_gen_brcondi_i32(TCG_COND_EQ, tmp, 4, skipexc);
         tcg_temp_free_i32(tmp);
-        gen_exception_insn(s, s->pc_curr, EXCP_INVSTATE, syn_uncategorized());
+        gen_exception_insn(s, 0, EXCP_INVSTATE, syn_uncategorized());
         gen_set_label(skipexc);
     }
 
@@ -9073,7 +9074,7 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
      * UsageFault exception.
      */
     if (arm_dc_feature(s, ARM_FEATURE_M)) {
-        gen_exception_insn(s, s->pc_curr, EXCP_INVSTATE, syn_uncategorized());
+        gen_exception_insn(s, 0, EXCP_INVSTATE, syn_uncategorized());
         return;
     }
 
@@ -9082,7 +9083,7 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
          * Illegal execution state. This has priority over BTI
          * exceptions, but comes after instruction abort exceptions.
          */
-        gen_exception_insn(s, s->pc_curr, EXCP_UDEF, syn_illegalstate());
+        gen_exception_insn(s, 0, EXCP_UDEF, syn_illegalstate());
         return;
     }
 
@@ -9647,7 +9648,7 @@ static void thumb_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
          * Illegal execution state. This has priority over BTI
          * exceptions, but comes after instruction abort exceptions.
          */
-        gen_exception_insn(dc, dc->pc_curr, EXCP_UDEF, syn_illegalstate());
+        gen_exception_insn(dc, 0, EXCP_UDEF, syn_illegalstate());
         return;
     }
 
@@ -9720,8 +9721,7 @@ static void thumb_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
          */
         tcg_remove_ops_after(dc->insn_eci_rewind);
         dc->condjmp = 0;
-        gen_exception_insn(dc, dc->pc_curr, EXCP_INVSTATE,
-                           syn_uncategorized());
+        gen_exception_insn(dc, 0, EXCP_INVSTATE, syn_uncategorized());
     }
 
     arm_post_translate_insn(dc);
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 5/9] target/arm: Remove gen_exception_internal_insn pc argument
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
                   ` (3 preceding siblings ...)
  2022-10-06  3:38 ` [PATCH v6 4/9] target/arm: Change gen_exception_insn* to work on displacements Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 6/9] target/arm: Change gen_jmp* to work on displacements Richard Henderson
                   ` (3 subsequent siblings)
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Philippe Mathieu-Daudé

In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.
Since we always pass dc->pc_curr, fold the arithmetic to zero displacement.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate-a64.c |  6 +++---
 target/arm/translate.c     | 10 +++++-----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 2621b3b36a..005fd767fb 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -340,9 +340,9 @@ static void gen_exception_internal(int excp)
     gen_helper_exception_internal(cpu_env, tcg_constant_i32(excp));
 }
 
-static void gen_exception_internal_insn(DisasContext *s, uint64_t pc, int excp)
+static void gen_exception_internal_insn(DisasContext *s, int excp)
 {
-    gen_a64_update_pc(s, pc - s->pc_curr);
+    gen_a64_update_pc(s, 0);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -2219,7 +2219,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
          * Secondly, "HLT 0xf000" is the A64 semihosting syscall instruction.
          */
         if (semihosting_enabled(s->current_el == 0) && imm16 == 0xf000) {
-            gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST);
+            gen_exception_internal_insn(s, EXCP_SEMIHOST);
         } else {
             unallocated_encoding(s);
         }
diff --git a/target/arm/translate.c b/target/arm/translate.c
index f9d3128656..e0b1d415a2 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -1078,10 +1078,10 @@ static inline void gen_smc(DisasContext *s)
     s->base.is_jmp = DISAS_SMC;
 }
 
-static void gen_exception_internal_insn(DisasContext *s, uint32_t pc, int excp)
+static void gen_exception_internal_insn(DisasContext *s, int excp)
 {
     gen_set_condexec(s);
-    gen_update_pc(s, pc - s->pc_curr);
+    gen_update_pc(s, 0);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -1173,7 +1173,7 @@ static inline void gen_hlt(DisasContext *s, int imm)
      */
     if (semihosting_enabled(s->current_el != 0) &&
         (imm == (s->thumb ? 0x3c : 0xf000))) {
-        gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST);
+        gen_exception_internal_insn(s, EXCP_SEMIHOST);
         return;
     }
 
@@ -6560,7 +6560,7 @@ static bool trans_BKPT(DisasContext *s, arg_BKPT *a)
     if (arm_dc_feature(s, ARM_FEATURE_M) &&
         semihosting_enabled(s->current_el == 0) &&
         (a->imm == 0xab)) {
-        gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST);
+        gen_exception_internal_insn(s, EXCP_SEMIHOST);
     } else {
         gen_exception_bkpt_insn(s, syn_aa32_bkpt(a->imm, false));
     }
@@ -8766,7 +8766,7 @@ static bool trans_SVC(DisasContext *s, arg_SVC *a)
     if (!arm_dc_feature(s, ARM_FEATURE_M) &&
         semihosting_enabled(s->current_el == 0) &&
         (a->imm == semihost_imm)) {
-        gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST);
+        gen_exception_internal_insn(s, EXCP_SEMIHOST);
     } else {
         gen_update_pc(s, curr_insn_len(s));
         s->svc_imm = a->imm;
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 6/9] target/arm: Change gen_jmp* to work on displacements
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
                   ` (4 preceding siblings ...)
  2022-10-06  3:38 ` [PATCH v6 5/9] target/arm: Remove gen_exception_internal_insn pc argument Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 7/9] target/arm: Introduce gen_pc_plus_diff for aarch64 Richard Henderson
                   ` (2 subsequent siblings)
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Peter Maydell

In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate.c | 37 +++++++++++++++++++++----------------
 1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/target/arm/translate.c b/target/arm/translate.c
index e0b1d415a2..336f151c4a 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -270,6 +270,12 @@ static uint32_t read_pc(DisasContext *s)
     return s->pc_curr + (s->thumb ? 4 : 8);
 }
 
+/* The pc_curr difference for an architectural jump. */
+static target_long jmp_diff(DisasContext *s, target_long diff)
+{
+    return diff + (s->thumb ? 4 : 8);
+}
+
 /* Set a variable to the value of a CPU register.  */
 void load_reg_var(DisasContext *s, TCGv_i32 var, int reg)
 {
@@ -2596,7 +2602,7 @@ static void gen_goto_ptr(void)
  * cpu_loop_exec. Any live exit_requests will be processed as we
  * enter the next TB.
  */
-static void gen_goto_tb(DisasContext *s, int n, int diff)
+static void gen_goto_tb(DisasContext *s, int n, target_long diff)
 {
     target_ulong dest = s->pc_curr + diff;
 
@@ -2612,10 +2618,8 @@ static void gen_goto_tb(DisasContext *s, int n, int diff)
 }
 
 /* Jump, specifying which TB number to use if we gen_goto_tb() */
-static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
+static void gen_jmp_tb(DisasContext *s, target_long diff, int tbno)
 {
-    int diff = dest - s->pc_curr;
-
     if (unlikely(s->ss_active)) {
         /* An indirect jump so that we still trigger the debug exception.  */
         gen_update_pc(s, diff);
@@ -2657,9 +2661,9 @@ static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
     }
 }
 
-static inline void gen_jmp(DisasContext *s, uint32_t dest)
+static inline void gen_jmp(DisasContext *s, target_long diff)
 {
-    gen_jmp_tb(s, dest, 0);
+    gen_jmp_tb(s, diff, 0);
 }
 
 static inline void gen_mulxy(TCGv_i32 t0, TCGv_i32 t1, int x, int y)
@@ -8326,7 +8330,7 @@ static bool trans_CLRM(DisasContext *s, arg_CLRM *a)
 
 static bool trans_B(DisasContext *s, arg_i *a)
 {
-    gen_jmp(s, read_pc(s) + a->imm);
+    gen_jmp(s, jmp_diff(s, a->imm));
     return true;
 }
 
@@ -8341,14 +8345,14 @@ static bool trans_B_cond_thumb(DisasContext *s, arg_ci *a)
         return true;
     }
     arm_skip_unless(s, a->cond);
-    gen_jmp(s, read_pc(s) + a->imm);
+    gen_jmp(s, jmp_diff(s, a->imm));
     return true;
 }
 
 static bool trans_BL(DisasContext *s, arg_i *a)
 {
     tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | s->thumb);
-    gen_jmp(s, read_pc(s) + a->imm);
+    gen_jmp(s, jmp_diff(s, a->imm));
     return true;
 }
 
@@ -8368,7 +8372,8 @@ static bool trans_BLX_i(DisasContext *s, arg_BLX_i *a)
     }
     tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | s->thumb);
     store_cpu_field_constant(!s->thumb, thumb);
-    gen_jmp(s, (read_pc(s) & ~3) + a->imm);
+    /* This jump is computed from an aligned PC: subtract off the low bits. */
+    gen_jmp(s, jmp_diff(s, a->imm - (s->pc_curr & 3)));
     return true;
 }
 
@@ -8529,10 +8534,10 @@ static bool trans_WLS(DisasContext *s, arg_WLS *a)
          * when we take this upcoming exit from this TB, so gen_jmp_tb() is OK.
          */
     }
-    gen_jmp_tb(s, s->base.pc_next, 1);
+    gen_jmp_tb(s, curr_insn_len(s), 1);
 
     gen_set_label(nextlabel);
-    gen_jmp(s, read_pc(s) + a->imm);
+    gen_jmp(s, jmp_diff(s, a->imm));
     return true;
 }
 
@@ -8612,7 +8617,7 @@ static bool trans_LE(DisasContext *s, arg_LE *a)
 
     if (a->f) {
         /* Loop-forever: just jump back to the loop start */
-        gen_jmp(s, read_pc(s) - a->imm);
+        gen_jmp(s, jmp_diff(s, -a->imm));
         return true;
     }
 
@@ -8643,7 +8648,7 @@ static bool trans_LE(DisasContext *s, arg_LE *a)
         tcg_temp_free_i32(decr);
     }
     /* Jump back to the loop start */
-    gen_jmp(s, read_pc(s) - a->imm);
+    gen_jmp(s, jmp_diff(s, -a->imm));
 
     gen_set_label(loopend);
     if (a->tp) {
@@ -8651,7 +8656,7 @@ static bool trans_LE(DisasContext *s, arg_LE *a)
         store_cpu_field(tcg_constant_i32(4), v7m.ltpsize);
     }
     /* End TB, continuing to following insn */
-    gen_jmp_tb(s, s->base.pc_next, 1);
+    gen_jmp_tb(s, curr_insn_len(s), 1);
     return true;
 }
 
@@ -8750,7 +8755,7 @@ static bool trans_CBZ(DisasContext *s, arg_CBZ *a)
     tcg_gen_brcondi_i32(a->nz ? TCG_COND_EQ : TCG_COND_NE,
                         tmp, 0, s->condlabel);
     tcg_temp_free_i32(tmp);
-    gen_jmp(s, read_pc(s) + a->imm);
+    gen_jmp(s, jmp_diff(s, a->imm));
     return true;
 }
 
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 7/9] target/arm: Introduce gen_pc_plus_diff for aarch64
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
                   ` (5 preceding siblings ...)
  2022-10-06  3:38 ` [PATCH v6 6/9] target/arm: Change gen_jmp* to work on displacements Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32 Richard Henderson
  2022-10-06  3:38 ` [PATCH v6 9/9] target/arm: Enable TARGET_TB_PCREL Richard Henderson
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Peter Maydell

In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate-a64.c | 41 +++++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 005fd767fb..28a417fb2b 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -148,9 +148,14 @@ static void reset_btype(DisasContext *s)
     }
 }
 
+static void gen_pc_plus_diff(DisasContext *s, TCGv_i64 dest, target_long diff)
+{
+    tcg_gen_movi_i64(dest, s->pc_curr + diff);
+}
+
 void gen_a64_update_pc(DisasContext *s, target_long diff)
 {
-    tcg_gen_movi_i64(cpu_pc, s->pc_curr + diff);
+    gen_pc_plus_diff(s, cpu_pc, diff);
 }
 
 /*
@@ -1368,7 +1373,7 @@ static void disas_uncond_b_imm(DisasContext *s, uint32_t insn)
 
     if (insn & (1U << 31)) {
         /* BL Branch with link */
-        tcg_gen_movi_i64(cpu_reg(s, 30), s->base.pc_next);
+        gen_pc_plus_diff(s, cpu_reg(s, 30), curr_insn_len(s));
     }
 
     /* B Branch / BL Branch with link */
@@ -2309,11 +2314,17 @@ static void disas_uncond_b_reg(DisasContext *s, uint32_t insn)
         default:
             goto do_unallocated;
         }
-        gen_a64_set_pc(s, dst);
         /* BLR also needs to load return address */
         if (opc == 1) {
-            tcg_gen_movi_i64(cpu_reg(s, 30), s->base.pc_next);
+            TCGv_i64 lr = cpu_reg(s, 30);
+            if (dst == lr) {
+                TCGv_i64 tmp = new_tmp_a64(s);
+                tcg_gen_mov_i64(tmp, dst);
+                dst = tmp;
+            }
+            gen_pc_plus_diff(s, lr, curr_insn_len(s));
         }
+        gen_a64_set_pc(s, dst);
         break;
 
     case 8: /* BRAA */
@@ -2336,11 +2347,17 @@ static void disas_uncond_b_reg(DisasContext *s, uint32_t insn)
         } else {
             dst = cpu_reg(s, rn);
         }
-        gen_a64_set_pc(s, dst);
         /* BLRAA also needs to load return address */
         if (opc == 9) {
-            tcg_gen_movi_i64(cpu_reg(s, 30), s->base.pc_next);
+            TCGv_i64 lr = cpu_reg(s, 30);
+            if (dst == lr) {
+                TCGv_i64 tmp = new_tmp_a64(s);
+                tcg_gen_mov_i64(tmp, dst);
+                dst = tmp;
+            }
+            gen_pc_plus_diff(s, lr, curr_insn_len(s));
         }
+        gen_a64_set_pc(s, dst);
         break;
 
     case 4: /* ERET */
@@ -2908,7 +2925,8 @@ static void disas_ld_lit(DisasContext *s, uint32_t insn)
 
     tcg_rt = cpu_reg(s, rt);
 
-    clean_addr = tcg_constant_i64(s->pc_curr + imm);
+    clean_addr = new_tmp_a64(s);
+    gen_pc_plus_diff(s, clean_addr, imm);
     if (is_vector) {
         do_fp_ld(s, rt, clean_addr, size);
     } else {
@@ -4252,23 +4270,22 @@ static void disas_ldst(DisasContext *s, uint32_t insn)
 static void disas_pc_rel_adr(DisasContext *s, uint32_t insn)
 {
     unsigned int page, rd;
-    uint64_t base;
-    uint64_t offset;
+    int64_t offset;
 
     page = extract32(insn, 31, 1);
     /* SignExtend(immhi:immlo) -> offset */
     offset = sextract64(insn, 5, 19);
     offset = offset << 2 | extract32(insn, 29, 2);
     rd = extract32(insn, 0, 5);
-    base = s->pc_curr;
 
     if (page) {
         /* ADRP (page based) */
-        base &= ~0xfff;
         offset <<= 12;
+        /* The page offset is ok for TARGET_TB_PCREL. */
+        offset -= s->pc_curr & 0xfff;
     }
 
-    tcg_gen_movi_i64(cpu_reg(s, rd), base + offset);
+    gen_pc_plus_diff(s, cpu_reg(s, rd), offset);
 }
 
 /*
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
                   ` (6 preceding siblings ...)
  2022-10-06  3:38 ` [PATCH v6 7/9] target/arm: Introduce gen_pc_plus_diff for aarch64 Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  2022-10-14 17:53   ` Peter Maydell
  2022-10-06  3:38 ` [PATCH v6 9/9] target/arm: Enable TARGET_TB_PCREL Richard Henderson
  8 siblings, 1 reply; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm, Philippe Mathieu-Daudé

In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate.c | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 336f151c4a..7c1e277732 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -276,11 +276,16 @@ static target_long jmp_diff(DisasContext *s, target_long diff)
     return diff + (s->thumb ? 4 : 8);
 }
 
+static void gen_pc_plus_diff(DisasContext *s, TCGv_i32 var, target_long diff)
+{
+    tcg_gen_movi_i32(var, s->pc_curr + diff);
+}
+
 /* Set a variable to the value of a CPU register.  */
 void load_reg_var(DisasContext *s, TCGv_i32 var, int reg)
 {
     if (reg == 15) {
-        tcg_gen_movi_i32(var, read_pc(s));
+        gen_pc_plus_diff(s, var, jmp_diff(s, 0));
     } else {
         tcg_gen_mov_i32(var, cpu_R[reg]);
     }
@@ -296,7 +301,8 @@ TCGv_i32 add_reg_for_lit(DisasContext *s, int reg, int ofs)
     TCGv_i32 tmp = tcg_temp_new_i32();
 
     if (reg == 15) {
-        tcg_gen_movi_i32(tmp, (read_pc(s) & ~3) + ofs);
+        /* This difference computes a page offset so ok for TARGET_TB_PCREL. */
+        gen_pc_plus_diff(s, tmp, (read_pc(s) & ~3) - s->pc_curr + ofs);
     } else {
         tcg_gen_addi_i32(tmp, cpu_R[reg], ofs);
     }
@@ -1159,7 +1165,7 @@ void unallocated_encoding(DisasContext *s)
 /* Force a TB lookup after an instruction that changes the CPU state.  */
 void gen_lookup_tb(DisasContext *s)
 {
-    tcg_gen_movi_i32(cpu_R[15], s->base.pc_next);
+    gen_pc_plus_diff(s, cpu_R[15], curr_insn_len(s));
     s->base.is_jmp = DISAS_EXIT;
 }
 
@@ -6483,7 +6489,7 @@ static bool trans_BLX_r(DisasContext *s, arg_BLX_r *a)
         return false;
     }
     tmp = load_reg(s, a->rm);
-    tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | s->thumb);
+    gen_pc_plus_diff(s, cpu_R[14], curr_insn_len(s) | s->thumb);
     gen_bx(s, tmp);
     return true;
 }
@@ -8351,7 +8357,7 @@ static bool trans_B_cond_thumb(DisasContext *s, arg_ci *a)
 
 static bool trans_BL(DisasContext *s, arg_i *a)
 {
-    tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | s->thumb);
+    gen_pc_plus_diff(s, cpu_R[14], curr_insn_len(s) | s->thumb);
     gen_jmp(s, jmp_diff(s, a->imm));
     return true;
 }
@@ -8370,7 +8376,7 @@ static bool trans_BLX_i(DisasContext *s, arg_BLX_i *a)
     if (s->thumb && (a->imm & 2)) {
         return false;
     }
-    tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | s->thumb);
+    gen_pc_plus_diff(s, cpu_R[14], curr_insn_len(s) | s->thumb);
     store_cpu_field_constant(!s->thumb, thumb);
     /* This jump is computed from an aligned PC: subtract off the low bits. */
     gen_jmp(s, jmp_diff(s, a->imm - (s->pc_curr & 3)));
@@ -8380,7 +8386,7 @@ static bool trans_BLX_i(DisasContext *s, arg_BLX_i *a)
 static bool trans_BL_BLX_prefix(DisasContext *s, arg_BL_BLX_prefix *a)
 {
     assert(!arm_dc_feature(s, ARM_FEATURE_THUMB2));
-    tcg_gen_movi_i32(cpu_R[14], read_pc(s) + (a->imm << 12));
+    gen_pc_plus_diff(s, cpu_R[14], jmp_diff(s, a->imm << 12));
     return true;
 }
 
@@ -8390,7 +8396,7 @@ static bool trans_BL_suffix(DisasContext *s, arg_BL_suffix *a)
 
     assert(!arm_dc_feature(s, ARM_FEATURE_THUMB2));
     tcg_gen_addi_i32(tmp, cpu_R[14], (a->imm << 1) | 1);
-    tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | 1);
+    gen_pc_plus_diff(s, cpu_R[14], curr_insn_len(s) | 1);
     gen_bx(s, tmp);
     return true;
 }
@@ -8406,7 +8412,7 @@ static bool trans_BLX_suffix(DisasContext *s, arg_BLX_suffix *a)
     tmp = tcg_temp_new_i32();
     tcg_gen_addi_i32(tmp, cpu_R[14], a->imm << 1);
     tcg_gen_andi_i32(tmp, tmp, 0xfffffffc);
-    tcg_gen_movi_i32(cpu_R[14], s->base.pc_next | 1);
+    gen_pc_plus_diff(s, cpu_R[14], curr_insn_len(s) | 1);
     gen_bx(s, tmp);
     return true;
 }
@@ -8729,10 +8735,11 @@ static bool op_tbranch(DisasContext *s, arg_tbranch *a, bool half)
     tcg_gen_add_i32(addr, addr, tmp);
 
     gen_aa32_ld_i32(s, tmp, addr, get_mem_index(s), half ? MO_UW : MO_UB);
-    tcg_temp_free_i32(addr);
 
     tcg_gen_add_i32(tmp, tmp, tmp);
-    tcg_gen_addi_i32(tmp, tmp, read_pc(s));
+    gen_pc_plus_diff(s, addr, jmp_diff(s, 0));
+    tcg_gen_add_i32(tmp, tmp, addr);
+    tcg_temp_free_i32(addr);
     store_reg(s, 15, tmp);
     return true;
 }
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v6 9/9] target/arm: Enable TARGET_TB_PCREL
  2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
                   ` (7 preceding siblings ...)
  2022-10-06  3:38 ` [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32 Richard Henderson
@ 2022-10-06  3:38 ` Richard Henderson
  8 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-06  3:38 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-arm

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/cpu-param.h     |  1 +
 target/arm/translate.h     | 19 ++++++++++++
 target/arm/cpu.c           | 23 +++++++-------
 target/arm/translate-a64.c | 37 ++++++++++++++++++-----
 target/arm/translate.c     | 62 ++++++++++++++++++++++++++++++--------
 5 files changed, 112 insertions(+), 30 deletions(-)

diff --git a/target/arm/cpu-param.h b/target/arm/cpu-param.h
index 68ffb12427..29c5fc4241 100644
--- a/target/arm/cpu-param.h
+++ b/target/arm/cpu-param.h
@@ -30,6 +30,7 @@
  */
 # define TARGET_PAGE_BITS_VARY
 # define TARGET_PAGE_BITS_MIN  10
+# define TARGET_TB_PCREL 1
 #endif
 
 #define NB_MMU_MODES 15
diff --git a/target/arm/translate.h b/target/arm/translate.h
index 4aa239e23c..1e5888fb6f 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -12,6 +12,25 @@ typedef struct DisasContext {
 
     /* The address of the current instruction being translated. */
     target_ulong pc_curr;
+    /*
+     * For TARGET_TB_PCREL, the full value of cpu_pc is not known
+     * (although the page offset is known).  For convenience, the
+     * translation loop uses the full virtual address that triggered
+     * the translation, from base.pc_start through pc_curr.
+     * For efficiency, we do not update cpu_pc for every instruction.
+     * Instead, pc_save has the value of pc_curr at the time of the
+     * last update to cpu_pc, which allows us to compute the addend
+     * needed to bring cpu_pc current: pc_curr - pc_save.
+     * If cpu_pc now contains the destination of an indirect branch,
+     * pc_save contains -1 to indicate that relative updates are no
+     * longer possible.
+     */
+    target_ulong pc_save;
+    /*
+     * Similarly, pc_cond_save contains the value of pc_save at the
+     * beginning of an AArch32 conditional instruction.
+     */
+    target_ulong pc_cond_save;
     target_ulong page_start;
     uint32_t insn;
     /* Nonzero if this instruction has been conditionally skipped.  */
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 94ca6f163f..0bc5e9b125 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -76,17 +76,18 @@ static vaddr arm_cpu_get_pc(CPUState *cs)
 void arm_cpu_synchronize_from_tb(CPUState *cs,
                                  const TranslationBlock *tb)
 {
-    ARMCPU *cpu = ARM_CPU(cs);
-    CPUARMState *env = &cpu->env;
-
-    /*
-     * It's OK to look at env for the current mode here, because it's
-     * never possible for an AArch64 TB to chain to an AArch32 TB.
-     */
-    if (is_a64(env)) {
-        env->pc = tb_pc(tb);
-    } else {
-        env->regs[15] = tb_pc(tb);
+    /* The program counter is always up to date with TARGET_TB_PCREL. */
+    if (!TARGET_TB_PCREL) {
+        CPUARMState *env = cs->env_ptr;
+        /*
+         * It's OK to look at env for the current mode here, because it's
+         * never possible for an AArch64 TB to chain to an AArch32 TB.
+         */
+        if (is_a64(env)) {
+            env->pc = tb_pc(tb);
+        } else {
+            env->regs[15] = tb_pc(tb);
+        }
     }
 }
 #endif /* CONFIG_TCG */
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 28a417fb2b..57cfc9f1a9 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -150,12 +150,18 @@ static void reset_btype(DisasContext *s)
 
 static void gen_pc_plus_diff(DisasContext *s, TCGv_i64 dest, target_long diff)
 {
-    tcg_gen_movi_i64(dest, s->pc_curr + diff);
+    assert(s->pc_save != -1);
+    if (TARGET_TB_PCREL) {
+        tcg_gen_addi_i64(dest, cpu_pc, (s->pc_curr - s->pc_save) + diff);
+    } else {
+        tcg_gen_movi_i64(dest, s->pc_curr + diff);
+    }
 }
 
 void gen_a64_update_pc(DisasContext *s, target_long diff)
 {
     gen_pc_plus_diff(s, cpu_pc, diff);
+    s->pc_save = s->pc_curr + diff;
 }
 
 /*
@@ -209,6 +215,7 @@ static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
      * then loading an address into the PC will clear out any tag.
      */
     gen_top_byte_ignore(s, cpu_pc, src, s->tbii);
+    s->pc_save = -1;
 }
 
 /*
@@ -347,16 +354,22 @@ static void gen_exception_internal(int excp)
 
 static void gen_exception_internal_insn(DisasContext *s, int excp)
 {
+    target_ulong pc_save = s->pc_save;
+
     gen_a64_update_pc(s, 0);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
+    s->pc_save = pc_save;
 }
 
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syndrome)
 {
+    target_ulong pc_save = s->pc_save;
+
     gen_a64_update_pc(s, 0);
     gen_helper_exception_bkpt_insn(cpu_env, tcg_constant_i32(syndrome));
     s->base.is_jmp = DISAS_NORETURN;
+    s->pc_save = pc_save;
 }
 
 static void gen_step_complete_exception(DisasContext *s)
@@ -385,11 +398,16 @@ static inline bool use_goto_tb(DisasContext *s, uint64_t dest)
 
 static void gen_goto_tb(DisasContext *s, int n, int64_t diff)
 {
-    uint64_t dest = s->pc_curr + diff;
+    target_ulong pc_save = s->pc_save;
 
-    if (use_goto_tb(s, dest)) {
-        tcg_gen_goto_tb(n);
-        gen_a64_update_pc(s, diff);
+    if (use_goto_tb(s, s->pc_curr + diff)) {
+        if (TARGET_TB_PCREL) {
+            gen_a64_update_pc(s, diff);
+            tcg_gen_goto_tb(n);
+        } else {
+            tcg_gen_goto_tb(n);
+            gen_a64_update_pc(s, diff);
+        }
         tcg_gen_exit_tb(s->base.tb, n);
         s->base.is_jmp = DISAS_NORETURN;
     } else {
@@ -401,6 +419,7 @@ static void gen_goto_tb(DisasContext *s, int n, int64_t diff)
             s->base.is_jmp = DISAS_NORETURN;
         }
     }
+    s->pc_save = pc_save;
 }
 
 static void init_tmp_a64_array(DisasContext *s)
@@ -14707,7 +14726,7 @@ static void aarch64_tr_init_disas_context(DisasContextBase *dcbase,
 
     dc->isar = &arm_cpu->isar;
     dc->condjmp = 0;
-
+    dc->pc_save = dc->base.pc_first;
     dc->aarch64 = true;
     dc->thumb = false;
     dc->sctlr_b = 0;
@@ -14789,8 +14808,12 @@ static void aarch64_tr_tb_start(DisasContextBase *db, CPUState *cpu)
 static void aarch64_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
 {
     DisasContext *dc = container_of(dcbase, DisasContext, base);
+    target_ulong pc_arg = dc->base.pc_next;
 
-    tcg_gen_insn_start(dc->base.pc_next, 0, 0);
+    if (TARGET_TB_PCREL) {
+        pc_arg &= ~TARGET_PAGE_MASK;
+    }
+    tcg_gen_insn_start(pc_arg, 0, 0);
     dc->insn_start = tcg_last_op();
 }
 
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 7c1e277732..ee14b70c8b 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -164,6 +164,7 @@ void arm_gen_condlabel(DisasContext *s)
     if (!s->condjmp) {
         s->condlabel = gen_new_label();
         s->condjmp = 1;
+        s->pc_cond_save = s->pc_save;
     }
 }
 
@@ -278,7 +279,12 @@ static target_long jmp_diff(DisasContext *s, target_long diff)
 
 static void gen_pc_plus_diff(DisasContext *s, TCGv_i32 var, target_long diff)
 {
-    tcg_gen_movi_i32(var, s->pc_curr + diff);
+    assert(s->pc_save != -1);
+    if (TARGET_TB_PCREL) {
+        tcg_gen_addi_i32(var, cpu_R[15], (s->pc_curr - s->pc_save) + diff);
+    } else {
+        tcg_gen_movi_i32(var, s->pc_curr + diff);
+    }
 }
 
 /* Set a variable to the value of a CPU register.  */
@@ -321,6 +327,7 @@ void store_reg(DisasContext *s, int reg, TCGv_i32 var)
          */
         tcg_gen_andi_i32(var, var, s->thumb ? ~1 : ~3);
         s->base.is_jmp = DISAS_JUMP;
+        s->pc_save = -1;
     } else if (reg == 13 && arm_dc_feature(s, ARM_FEATURE_M)) {
         /* For M-profile SP bits [1:0] are always zero */
         tcg_gen_andi_i32(var, var, ~3);
@@ -786,7 +793,8 @@ void gen_set_condexec(DisasContext *s)
 
 void gen_update_pc(DisasContext *s, target_long diff)
 {
-    tcg_gen_movi_i32(cpu_R[15], s->pc_curr + diff);
+    gen_pc_plus_diff(s, cpu_R[15], diff);
+    s->pc_save = s->pc_curr + diff;
 }
 
 /* Set PC and Thumb state from var.  var is marked as dead.  */
@@ -796,6 +804,7 @@ static inline void gen_bx(DisasContext *s, TCGv_i32 var)
     tcg_gen_andi_i32(cpu_R[15], var, ~1);
     tcg_gen_andi_i32(var, var, 1);
     store_cpu_field(var, thumb);
+    s->pc_save = -1;
 }
 
 /*
@@ -1118,6 +1127,8 @@ static void gen_exception(int excp, uint32_t syndrome)
 static void gen_exception_insn_el_v(DisasContext *s, target_long pc_diff,
                                     int excp, uint32_t syn, TCGv_i32 tcg_el)
 {
+    target_ulong pc_save = s->pc_save;
+
     if (s->aarch64) {
         gen_a64_update_pc(s, pc_diff);
     } else {
@@ -1126,6 +1137,7 @@ static void gen_exception_insn_el_v(DisasContext *s, target_long pc_diff,
     }
     gen_exception_el_v(excp, syn, tcg_el);
     s->base.is_jmp = DISAS_NORETURN;
+    s->pc_save = pc_save;
 }
 
 void gen_exception_insn_el(DisasContext *s, target_long pc_diff, int excp,
@@ -1138,6 +1150,8 @@ void gen_exception_insn_el(DisasContext *s, target_long pc_diff, int excp,
 void gen_exception_insn(DisasContext *s, target_long pc_diff,
                         int excp, uint32_t syn)
 {
+    target_ulong pc_save = s->pc_save;
+
     if (s->aarch64) {
         gen_a64_update_pc(s, pc_diff);
     } else {
@@ -1146,6 +1160,7 @@ void gen_exception_insn(DisasContext *s, target_long pc_diff,
     }
     gen_exception(excp, syn);
     s->base.is_jmp = DISAS_NORETURN;
+    s->pc_save = pc_save;
 }
 
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syn)
@@ -2610,11 +2625,14 @@ static void gen_goto_ptr(void)
  */
 static void gen_goto_tb(DisasContext *s, int n, target_long diff)
 {
-    target_ulong dest = s->pc_curr + diff;
-
-    if (translator_use_goto_tb(&s->base, dest)) {
-        tcg_gen_goto_tb(n);
-        gen_update_pc(s, diff);
+    if (translator_use_goto_tb(&s->base, s->pc_curr + diff)) {
+        if (TARGET_TB_PCREL) {
+            gen_update_pc(s, diff);
+            tcg_gen_goto_tb(n);
+        } else {
+            tcg_gen_goto_tb(n);
+            gen_update_pc(s, diff);
+        }
         tcg_gen_exit_tb(s->base.tb, n);
     } else {
         gen_update_pc(s, diff);
@@ -2626,10 +2644,13 @@ static void gen_goto_tb(DisasContext *s, int n, target_long diff)
 /* Jump, specifying which TB number to use if we gen_goto_tb() */
 static void gen_jmp_tb(DisasContext *s, target_long diff, int tbno)
 {
+    target_ulong pc_save = s->pc_save;
+
     if (unlikely(s->ss_active)) {
         /* An indirect jump so that we still trigger the debug exception.  */
         gen_update_pc(s, diff);
         s->base.is_jmp = DISAS_JUMP;
+        s->pc_save = pc_save;
         return;
     }
     switch (s->base.is_jmp) {
@@ -2665,6 +2686,7 @@ static void gen_jmp_tb(DisasContext *s, target_long diff, int tbno)
          */
         g_assert_not_reached();
     }
+    s->pc_save = pc_save;
 }
 
 static inline void gen_jmp(DisasContext *s, target_long diff)
@@ -9326,7 +9348,7 @@ static void arm_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
 
     dc->isar = &cpu->isar;
     dc->condjmp = 0;
-
+    dc->pc_save = dc->base.pc_first;
     dc->aarch64 = false;
     dc->thumb = EX_TBFLAG_AM32(tb_flags, THUMB);
     dc->be_data = EX_TBFLAG_ANY(tb_flags, BE_DATA) ? MO_BE : MO_LE;
@@ -9481,13 +9503,17 @@ static void arm_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
      * fields here.
      */
     uint32_t condexec_bits;
+    target_ulong pc_arg = dc->base.pc_next;
 
+    if (TARGET_TB_PCREL) {
+        pc_arg &= ~TARGET_PAGE_MASK;
+    }
     if (dc->eci) {
         condexec_bits = dc->eci << 4;
     } else {
         condexec_bits = (dc->condexec_cond << 4) | (dc->condexec_mask >> 1);
     }
-    tcg_gen_insn_start(dc->base.pc_next, condexec_bits, 0);
+    tcg_gen_insn_start(pc_arg, condexec_bits, 0);
     dc->insn_start = tcg_last_op();
 }
 
@@ -9530,7 +9556,10 @@ static bool arm_check_ss_active(DisasContext *dc)
 
 static void arm_post_translate_insn(DisasContext *dc)
 {
-    if (dc->condjmp && !dc->base.is_jmp) {
+    if (dc->condjmp && dc->base.is_jmp == DISAS_NEXT) {
+        if (dc->pc_save != dc->pc_cond_save) {
+            gen_update_pc(dc, dc->pc_cond_save - dc->pc_save);
+        }
         gen_set_label(dc->condlabel);
         dc->condjmp = 0;
     }
@@ -9860,6 +9889,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
 
     if (dc->condjmp) {
         /* "Condition failed" instruction codepath for the branch/trap insn */
+        dc->pc_save = dc->pc_cond_save;
         gen_set_label(dc->condlabel);
         gen_set_condexec(dc);
         if (unlikely(dc->ss_active)) {
@@ -9922,11 +9952,19 @@ void restore_state_to_opc(CPUARMState *env, TranslationBlock *tb,
                           target_ulong *data)
 {
     if (is_a64(env)) {
-        env->pc = data[0];
+        if (TARGET_TB_PCREL) {
+            env->pc = (env->pc & TARGET_PAGE_MASK) | data[0];
+        } else {
+            env->pc = data[0];
+        }
         env->condexec_bits = 0;
         env->exception.syndrome = data[2] << ARM_INSN_START_WORD2_SHIFT;
     } else {
-        env->regs[15] = data[0];
+        if (TARGET_TB_PCREL) {
+            env->regs[15] = (env->regs[15] & TARGET_PAGE_MASK) | data[0];
+        } else {
+            env->regs[15] = data[0];
+        }
         env->condexec_bits = data[1];
         env->exception.syndrome = data[2] << ARM_INSN_START_WORD2_SHIFT;
     }
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32
  2022-10-06  3:38 ` [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32 Richard Henderson
@ 2022-10-14 17:53   ` Peter Maydell
  2022-10-14 18:46     ` Richard Henderson
  0 siblings, 1 reply; 12+ messages in thread
From: Peter Maydell @ 2022-10-14 17:53 UTC (permalink / raw)
  To: Richard Henderson; +Cc: qemu-devel, qemu-arm, Philippe Mathieu-Daudé

On Thu, 6 Oct 2022 at 04:55, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.
>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> @@ -296,7 +301,8 @@ TCGv_i32 add_reg_for_lit(DisasContext *s, int reg, int ofs)
>      TCGv_i32 tmp = tcg_temp_new_i32();
>
>      if (reg == 15) {
> -        tcg_gen_movi_i32(tmp, (read_pc(s) & ~3) + ofs);
> +        /* This difference computes a page offset so ok for TARGET_TB_PCREL. */
> +        gen_pc_plus_diff(s, tmp, (read_pc(s) & ~3) - s->pc_curr + ofs);
>      } else {
>          tcg_gen_addi_i32(tmp, cpu_R[reg], ofs);
>      }

This is still doing the pc - pc thing -- I guess my comment on v5
crossed in the mail with your v6 repost.

Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32
  2022-10-14 17:53   ` Peter Maydell
@ 2022-10-14 18:46     ` Richard Henderson
  0 siblings, 0 replies; 12+ messages in thread
From: Richard Henderson @ 2022-10-14 18:46 UTC (permalink / raw)
  To: Peter Maydell; +Cc: qemu-devel, qemu-arm, Philippe Mathieu-Daudé

On 10/15/22 04:53, Peter Maydell wrote:
> On Thu, 6 Oct 2022 at 04:55, Richard Henderson
> <richard.henderson@linaro.org> wrote:
>>
>> In preparation for TARGET_TB_PCREL, reduce reliance on absolute values.
>>
>> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
>> @@ -296,7 +301,8 @@ TCGv_i32 add_reg_for_lit(DisasContext *s, int reg, int ofs)
>>       TCGv_i32 tmp = tcg_temp_new_i32();
>>
>>       if (reg == 15) {
>> -        tcg_gen_movi_i32(tmp, (read_pc(s) & ~3) + ofs);
>> +        /* This difference computes a page offset so ok for TARGET_TB_PCREL. */
>> +        gen_pc_plus_diff(s, tmp, (read_pc(s) & ~3) - s->pc_curr + ofs);
>>       } else {
>>           tcg_gen_addi_i32(tmp, cpu_R[reg], ofs);
>>       }
> 
> This is still doing the pc - pc thing -- I guess my comment on v5
> crossed in the mail with your v6 repost.

Yes, v6 was posted a couple of days beforehand.
I'll do a v7 with the change soon.


r~



^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2022-10-14 18:49 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-10-06  3:38 [PATCH v6 0/9] target/arm: pc-relative translation blocks Richard Henderson
2022-10-06  3:38 ` [PATCH v6 1/9] target/arm: Introduce curr_insn_len Richard Henderson
2022-10-06  3:38 ` [PATCH v6 2/9] target/arm: Change gen_goto_tb to work on displacements Richard Henderson
2022-10-06  3:38 ` [PATCH v6 3/9] target/arm: Change gen_*set_pc_im to gen_*update_pc Richard Henderson
2022-10-06  3:38 ` [PATCH v6 4/9] target/arm: Change gen_exception_insn* to work on displacements Richard Henderson
2022-10-06  3:38 ` [PATCH v6 5/9] target/arm: Remove gen_exception_internal_insn pc argument Richard Henderson
2022-10-06  3:38 ` [PATCH v6 6/9] target/arm: Change gen_jmp* to work on displacements Richard Henderson
2022-10-06  3:38 ` [PATCH v6 7/9] target/arm: Introduce gen_pc_plus_diff for aarch64 Richard Henderson
2022-10-06  3:38 ` [PATCH v6 8/9] target/arm: Introduce gen_pc_plus_diff for aarch32 Richard Henderson
2022-10-14 17:53   ` Peter Maydell
2022-10-14 18:46     ` Richard Henderson
2022-10-06  3:38 ` [PATCH v6 9/9] target/arm: Enable TARGET_TB_PCREL Richard Henderson

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).