[Qemu-devel] [PATCH] target-xtensa: make sar_m32 global instead of local temp

[Max Filippov <jcmvbkbc@gmail.com>]

This fixes the following assertion caused by local temp reaching the end
of TB in discarded state:

  qemu-system-xtensa: tcg/tcg.c:1665: temp_save: Assertion `s->temps[temp].val_type == 2 || s->temps[temp].fixed_reg' failed.
  Aborted

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
---
 target-xtensa/cpu.h       |    1 +
 target-xtensa/translate.c |   28 ++++++++--------------------
 2 files changed, 9 insertions(+), 20 deletions(-)

diff --git a/target-xtensa/cpu.h b/target-xtensa/cpu.h
index 74e9888..f021a9a 100644
--- a/target-xtensa/cpu.h
+++ b/target-xtensa/cpu.h
@@ -323,6 +323,7 @@ typedef struct CPUXtensaState {
     const XtensaConfig *config;
     uint32_t regs[16];
     uint32_t pc;
+    uint32_t sar_m32;
     uint32_t sregs[256];
     uint32_t uregs[256];
     uint32_t phys_regs[MAX_NAREG];
diff --git a/target-xtensa/translate.c b/target-xtensa/translate.c
index e5a3f49..4f3cf32 100644
--- a/target-xtensa/translate.c
+++ b/target-xtensa/translate.c
@@ -56,8 +56,6 @@ typedef struct DisasContext {
 
     bool sar_5bit;
     bool sar_m32_5bit;
-    bool sar_m32_allocated;
-    TCGv_i32 sar_m32;
 
     uint32_t ccount_delta;
     unsigned used_window;
@@ -71,6 +69,7 @@ typedef struct DisasContext {
 
 static TCGv_ptr cpu_env;
 static TCGv_i32 cpu_pc;
+static TCGv_i32 cpu_sar_m32;
 static TCGv_i32 cpu_R[16];
 static TCGv_i32 cpu_FR[16];
 static TCGv_i32 cpu_SR[256];
@@ -169,6 +168,8 @@ void xtensa_translate_init(void)
     cpu_env = tcg_global_reg_new_ptr(TCG_AREG0, "env");
     cpu_pc = tcg_global_mem_new_i32(TCG_AREG0,
             offsetof(CPUXtensaState, pc), "pc");
+    cpu_sar_m32 = tcg_global_mem_new_i32(TCG_AREG0,
+            offsetof(CPUXtensaState, sar_m32), "sar_m32");
 
     for (i = 0; i < 16; i++) {
         cpu_R[i] = tcg_global_mem_new_i32(TCG_AREG0,
@@ -230,21 +231,13 @@ static void init_sar_tracker(DisasContext *dc)
 {
     dc->sar_5bit = false;
     dc->sar_m32_5bit = false;
-    dc->sar_m32_allocated = false;
-}
-
-static void reset_sar_tracker(DisasContext *dc)
-{
-    if (dc->sar_m32_allocated) {
-        tcg_temp_free(dc->sar_m32);
-    }
 }
 
 static void gen_right_shift_sar(DisasContext *dc, TCGv_i32 sa)
 {
     tcg_gen_andi_i32(cpu_SR[SAR], sa, 0x1f);
     if (dc->sar_m32_5bit) {
-        tcg_gen_discard_i32(dc->sar_m32);
+        tcg_gen_discard_i32(cpu_sar_m32);
     }
     dc->sar_5bit = true;
     dc->sar_m32_5bit = false;
@@ -253,12 +246,8 @@ static void gen_right_shift_sar(DisasContext *dc, TCGv_i32 sa)
 static void gen_left_shift_sar(DisasContext *dc, TCGv_i32 sa)
 {
     TCGv_i32 tmp = tcg_const_i32(32);
-    if (!dc->sar_m32_allocated) {
-        dc->sar_m32 = tcg_temp_local_new_i32();
-        dc->sar_m32_allocated = true;
-    }
-    tcg_gen_andi_i32(dc->sar_m32, sa, 0x1f);
-    tcg_gen_sub_i32(cpu_SR[SAR], tmp, dc->sar_m32);
+    tcg_gen_andi_i32(cpu_sar_m32, sa, 0x1f);
+    tcg_gen_sub_i32(cpu_SR[SAR], tmp, cpu_sar_m32);
     dc->sar_5bit = false;
     dc->sar_m32_5bit = true;
     tcg_temp_free(tmp);
@@ -498,7 +487,7 @@ static void gen_wsr_sar(DisasContext *dc, uint32_t sr, TCGv_i32 s)
 {
     tcg_gen_andi_i32(cpu_SR[sr], s, 0x3f);
     if (dc->sar_m32_5bit) {
-        tcg_gen_discard_i32(dc->sar_m32);
+        tcg_gen_discard_i32(cpu_sar_m32);
     }
     dc->sar_5bit = false;
     dc->sar_m32_5bit = false;
@@ -1483,7 +1472,7 @@ static void disas_xtensa_insn(CPUXtensaState *env, DisasContext *dc)
             case 10: /*SLL*/
                 gen_window_check2(dc, RRR_R, RRR_S);
                 if (dc->sar_m32_5bit) {
-                    tcg_gen_shl_i32(cpu_R[RRR_R], cpu_R[RRR_S], dc->sar_m32);
+                    tcg_gen_shl_i32(cpu_R[RRR_R], cpu_R[RRR_S], cpu_sar_m32);
                 } else {
                     TCGv_i64 v = tcg_temp_new_i64();
                     TCGv_i32 s = tcg_const_i32(32);
@@ -2947,7 +2936,6 @@ static void gen_intermediate_code_internal(
             tcg_ctx.gen_opc_ptr < gen_opc_end);
 
     reset_litbase(&dc);
-    reset_sar_tracker(&dc);
     if (dc.icount) {
         tcg_temp_free(dc.next_icount);
     }
-- 
1.7.7.6