[Qemu-devel] [PATCH 27/26] tcg-aarch64: Introduce tcg_out_insn_3312, _3310, _3313

[Richard Henderson <rth@twiddle.net>]

Merge TCGMemOp size, AArch64LdstType type and a few stray opcode bits
into a single I3312_* argument, eliminating some magic numbers from
helper functions.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 tcg/aarch64/tcg-target.c | 129 ++++++++++++++++++++++++++++-------------------
 1 file changed, 76 insertions(+), 53 deletions(-)
---

I'm not really sure how much clearer this is, especially since we do
have to re-extract the size within tcg_out_ldst.  But it does at least
eliminate some of the magic numbers within the helpers.

Thoughts?


r~



diff --git a/tcg/aarch64/tcg-target.c b/tcg/aarch64/tcg-target.c
index ab4cd25..324a452 100644
--- a/tcg/aarch64/tcg-target.c
+++ b/tcg/aarch64/tcg-target.c
@@ -271,6 +271,28 @@ typedef enum {
     I3207_BLR       = 0xd63f0000,
     I3207_RET       = 0xd65f0000,
 
+    /* Load/store register.  Described here as 3.3.12, but the helper
+       that emits them can transform to 3.3.10 or 3.3.13.  */
+    I3312_STRB      = 0x38000000 | LDST_ST << 22 | MO_8 << 30,
+    I3312_STRH      = 0x38000000 | LDST_ST << 22 | MO_16 << 30,
+    I3312_STRW      = 0x38000000 | LDST_ST << 22 | MO_32 << 30,
+    I3312_STRX      = 0x38000000 | LDST_ST << 22 | MO_64 << 30,
+
+    I3312_LDRB      = 0x38000000 | LDST_LD << 22 | MO_8 << 30,
+    I3312_LDRH      = 0x38000000 | LDST_LD << 22 | MO_16 << 30,
+    I3312_LDRW      = 0x38000000 | LDST_LD << 22 | MO_32 << 30,
+    I3312_LDRX      = 0x38000000 | LDST_LD << 22 | MO_64 << 30,
+
+    I3312_LDRSBW    = 0x38000000 | LDST_LD_S_W << 22 | MO_8 << 30,
+    I3312_LDRSHW    = 0x38000000 | LDST_LD_S_W << 22 | MO_16 << 30,
+
+    I3312_LDRSBX    = 0x38000000 | LDST_LD_S_X << 22 | MO_8 << 30,
+    I3312_LDRSHX    = 0x38000000 | LDST_LD_S_X << 22 | MO_16 << 30,
+    I3312_LDRSWX    = 0x38000000 | LDST_LD_S_X << 22 | MO_32 << 30,
+
+    I3312_TO_I3310  = 0x00206800,
+    I3312_TO_I3313  = 0x01000000,
+
     /* Load/store register pair instructions.  */
     I3314_LDP       = 0x28400000,
     I3314_STP       = 0x28000000,
@@ -482,21 +504,25 @@ static void tcg_out_insn_3509(TCGContext *s, AArch64Insn insn, TCGType ext,
     tcg_out32(s, insn | ext << 31 | rm << 16 | ra << 10 | rn << 5 | rd);
 }
 
+static void tcg_out_insn_3310(TCGContext *s, AArch64Insn insn,
+                              TCGReg rd, TCGReg base, TCGReg regoff)
+{
+    /* Note the AArch64Insn constants above are for C3.3.12.  Adjust.  */
+    tcg_out32(s, insn | I3312_TO_I3310 | regoff << 16 | base << 5 | rd);
+}
+
 
-static void tcg_out_ldst_9(TCGContext *s, TCGMemOp size, AArch64LdstType type,
-                           TCGReg rd, TCGReg rn, intptr_t offset)
+static void tcg_out_insn_3312(TCGContext *s, AArch64Insn insn,
+                              TCGReg rd, TCGReg rn, intptr_t offset)
 {
-    /* use LDUR with BASE register with 9bit signed unscaled offset */
-    tcg_out32(s, 0x38000000 | size << 30 | type << 22
-              | (offset & 0x1ff) << 12 | rn << 5 | rd);
+    tcg_out32(s, insn | (offset & 0x1ff) << 12 | rn << 5 | rd);
 }
 
-/* tcg_out_ldst_12 expects a scaled unsigned immediate offset */
-static void tcg_out_ldst_12(TCGContext *s, TCGMemOp size, AArch64LdstType type,
-                            TCGReg rd, TCGReg rn, tcg_target_ulong scaled_uimm)
+static void tcg_out_insn_3313(TCGContext *s, AArch64Insn insn,
+                              TCGReg rd, TCGReg rn, uintptr_t scaled_uimm)
 {
-    tcg_out32(s, 0x39000000 | size << 30 | type << 22
-              | scaled_uimm << 10 | rn << 5 | rd);
+    /* Note the AArch64Insn constants above are for C3.3.12.  Adjust.  */
+    tcg_out32(s, insn | I3312_TO_I3313 | scaled_uimm << 10 | rn << 5 | rd);
 }
 
 /* Register to register move using ORR (shifted register with no shift). */
@@ -634,35 +660,32 @@ static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd,
     }
 }
 
-static void tcg_out_ldst_r(TCGContext *s, TCGMemOp size, AArch64LdstType type,
-                           TCGReg rd, TCGReg base, TCGReg regoff)
-{
-    tcg_out32(s, 0x38206800 | size << 30 | type << 22
-              | regoff << 16 | base << 5 | rd);
-}
+/* Define something more legible for general use.  */
+#define tcg_out_ldst_r  tcg_out_insn_3310
 
-/* solve the whole ldst problem */
-static void tcg_out_ldst(TCGContext *s, TCGMemOp size, AArch64LdstType type,
+static void tcg_out_ldst(TCGContext *s, AArch64Insn insn,
                          TCGReg rd, TCGReg rn, intptr_t offset)
 {
+    TCGMemOp size = (uint32_t)insn >> 30;
+
     /* If the offset is naturally aligned and in range, then we can
        use the scaled uimm12 encoding */
     if (offset >= 0 && !(offset & ((1 << size) - 1))) {
-        tcg_target_ulong scaled_uimm = offset >> size;
+        uintptr_t scaled_uimm = offset >> size;
         if (scaled_uimm <= 0xfff) {
-            tcg_out_ldst_12(s, size, type, rd, rn, scaled_uimm);
+            tcg_out_insn_3313(s, insn, rd, rn, scaled_uimm);
             return;
         }
     }
 
     if (offset >= -256 && offset < 256) {
-        tcg_out_ldst_9(s, size, type, rd, rn, offset);
+        tcg_out_insn_3312(s, insn, rd, rn, offset);
         return;
     }
 
     /* Worst-case scenario, move offset to temp register, use reg offset.  */
     tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_TMP, offset);
-    tcg_out_ldst_r(s, size, type, rd, rn, TCG_REG_TMP);
+    tcg_out_ldst_r(s, insn, rd, rn, TCG_REG_TMP);
 }
 
 static inline void tcg_out_mov(TCGContext *s,
@@ -676,14 +699,14 @@ static inline void tcg_out_mov(TCGContext *s,
 static inline void tcg_out_ld(TCGContext *s, TCGType type, TCGReg arg,
                               TCGReg arg1, intptr_t arg2)
 {
-    tcg_out_ldst(s, type == TCG_TYPE_I64 ? MO_64 : MO_32, LDST_LD,
+    tcg_out_ldst(s, type == TCG_TYPE_I32 ? I3312_LDRW : I3312_LDRX,
                  arg, arg1, arg2);
 }
 
 static inline void tcg_out_st(TCGContext *s, TCGType type, TCGReg arg,
                               TCGReg arg1, intptr_t arg2)
 {
-    tcg_out_ldst(s, type == TCG_TYPE_I64 ? MO_64 : MO_32, LDST_ST,
+    tcg_out_ldst(s, type == TCG_TYPE_I32 ? I3312_STRW : I3312_STRX,
                  arg, arg1, arg2);
 }
 
@@ -1081,12 +1104,12 @@ static void tcg_out_tlb_read(TCGContext *s, TCGReg addr_reg, TCGMemOp s_bits,
 
     /* Merge "low bits" from tlb offset, load the tlb comparator into X0.
        X0 = load [X2 + (tlb_offset & 0x000fff)] */
-    tcg_out_ldst(s, TARGET_LONG_BITS == 64 ? MO_64 : MO_32,
-                 LDST_LD, TCG_REG_X0, TCG_REG_X2, tlb_offset & 0xfff);
+    tcg_out_ldst(s, TARGET_LONG_BITS == 32 ? I3312_LDRW : I3312_LDRX,
+                 TCG_REG_X0, TCG_REG_X2, tlb_offset & 0xfff);
 
     /* Load the tlb addend. Do that early to avoid stalling.
        X1 = load [X2 + (tlb_offset & 0xfff) + offsetof(addend)] */
-    tcg_out_ldst(s, MO_64, LDST_LD, TCG_REG_X1, TCG_REG_X2,
+    tcg_out_ldst(s, I3312_LDRX, TCG_REG_X1, TCG_REG_X2,
                  (tlb_offset & 0xfff) + (offsetof(CPUTLBEntry, addend)) -
                  (is_read ? offsetof(CPUTLBEntry, addr_read)
                   : offsetof(CPUTLBEntry, addr_write)));
@@ -1108,43 +1131,43 @@ static void tcg_out_qemu_ld_direct(TCGContext *s, TCGMemOp memop,
 
     switch (memop & MO_SSIZE) {
     case MO_UB:
-        tcg_out_ldst_r(s, MO_8, LDST_LD, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_LDRB, data_r, addr_r, off_r);
         break;
     case MO_SB:
-        tcg_out_ldst_r(s, MO_8, LDST_LD_S_X, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_LDRSBX, data_r, addr_r, off_r);
         break;
     case MO_UW:
-        tcg_out_ldst_r(s, MO_16, LDST_LD, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_LDRH, data_r, addr_r, off_r);
         if (bswap) {
             tcg_out_rev16(s, TCG_TYPE_I32, data_r, data_r);
         }
         break;
     case MO_SW:
         if (bswap) {
-            tcg_out_ldst_r(s, MO_16, LDST_LD, data_r, addr_r, off_r);
+            tcg_out_ldst_r(s, I3312_LDRH, data_r, addr_r, off_r);
             tcg_out_rev16(s, TCG_TYPE_I32, data_r, data_r);
             tcg_out_sxt(s, TCG_TYPE_I64, MO_16, data_r, data_r);
         } else {
-            tcg_out_ldst_r(s, MO_16, LDST_LD_S_X, data_r, addr_r, off_r);
+            tcg_out_ldst_r(s, I3312_LDRSHX, data_r, addr_r, off_r);
         }
         break;
     case MO_UL:
-        tcg_out_ldst_r(s, MO_32, LDST_LD, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_LDRW, data_r, addr_r, off_r);
         if (bswap) {
             tcg_out_rev(s, TCG_TYPE_I32, data_r, data_r);
         }
         break;
     case MO_SL:
         if (bswap) {
-            tcg_out_ldst_r(s, MO_32, LDST_LD, data_r, addr_r, off_r);
+            tcg_out_ldst_r(s, I3312_LDRW, data_r, addr_r, off_r);
             tcg_out_rev(s, TCG_TYPE_I32, data_r, data_r);
             tcg_out_sxt(s, TCG_TYPE_I64, MO_32, data_r, data_r);
         } else {
-            tcg_out_ldst_r(s, MO_32, LDST_LD_S_X, data_r, addr_r, off_r);
+            tcg_out_ldst_r(s, I3312_LDRSWX, data_r, addr_r, off_r);
         }
         break;
     case MO_Q:
-        tcg_out_ldst_r(s, MO_64, LDST_LD, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_LDRX, data_r, addr_r, off_r);
         if (bswap) {
             tcg_out_rev(s, TCG_TYPE_I64, data_r, data_r);
         }
@@ -1161,28 +1184,28 @@ static void tcg_out_qemu_st_direct(TCGContext *s, TCGMemOp memop,
 
     switch (memop & MO_SIZE) {
     case MO_8:
-        tcg_out_ldst_r(s, MO_8, LDST_ST, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_STRB, data_r, addr_r, off_r);
         break;
     case MO_16:
         if (bswap && data_r != TCG_REG_XZR) {
             tcg_out_rev16(s, TCG_TYPE_I32, TCG_REG_TMP, data_r);
             data_r = TCG_REG_TMP;
         }
-        tcg_out_ldst_r(s, MO_16, LDST_ST, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_STRH, data_r, addr_r, off_r);
         break;
     case MO_32:
         if (bswap && data_r != TCG_REG_XZR) {
             tcg_out_rev(s, TCG_TYPE_I32, TCG_REG_TMP, data_r);
             data_r = TCG_REG_TMP;
         }
-        tcg_out_ldst_r(s, MO_32, LDST_ST, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_STRW, data_r, addr_r, off_r);
         break;
     case MO_64:
         if (bswap && data_r != TCG_REG_XZR) {
             tcg_out_rev(s, TCG_TYPE_I64, TCG_REG_TMP, data_r);
             data_r = TCG_REG_TMP;
         }
-        tcg_out_ldst_r(s, MO_64, LDST_ST, data_r, addr_r, off_r);
+        tcg_out_ldst_r(s, I3312_STRX, data_r, addr_r, off_r);
         break;
     default:
         tcg_abort();
@@ -1275,49 +1298,49 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc,
 
     case INDEX_op_ld8u_i32:
     case INDEX_op_ld8u_i64:
-        tcg_out_ldst(s, MO_8, LDST_LD, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRB, a0, a1, a2);
         break;
     case INDEX_op_ld8s_i32:
-        tcg_out_ldst(s, MO_8, LDST_LD_S_W, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRSBW, a0, a1, a2);
         break;
     case INDEX_op_ld8s_i64:
-        tcg_out_ldst(s, MO_8, LDST_LD_S_X, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRSBX, a0, a1, a2);
         break;
     case INDEX_op_ld16u_i32:
     case INDEX_op_ld16u_i64:
-        tcg_out_ldst(s, MO_16, LDST_LD, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRH, a0, a1, a2);
         break;
     case INDEX_op_ld16s_i32:
-        tcg_out_ldst(s, MO_16, LDST_LD_S_W, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRSHW, a0, a1, a2);
         break;
     case INDEX_op_ld16s_i64:
-        tcg_out_ldst(s, MO_16, LDST_LD_S_X, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRSHX, a0, a1, a2);
         break;
     case INDEX_op_ld_i32:
     case INDEX_op_ld32u_i64:
-        tcg_out_ldst(s, MO_32, LDST_LD, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRW, a0, a1, a2);
         break;
     case INDEX_op_ld32s_i64:
-        tcg_out_ldst(s, MO_32, LDST_LD_S_X, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRSWX, a0, a1, a2);
         break;
     case INDEX_op_ld_i64:
-        tcg_out_ldst(s, MO_64, LDST_LD, a0, a1, a2);
+        tcg_out_ldst(s, I3312_LDRX, a0, a1, a2);
         break;
 
     case INDEX_op_st8_i32:
     case INDEX_op_st8_i64:
-        tcg_out_ldst(s, MO_8, LDST_ST, REG0(0), a1, a2);
+        tcg_out_ldst(s, I3312_STRB, REG0(0), a1, a2);
         break;
     case INDEX_op_st16_i32:
     case INDEX_op_st16_i64:
-        tcg_out_ldst(s, MO_16, LDST_ST, REG0(0), a1, a2);
+        tcg_out_ldst(s, I3312_STRH, REG0(0), a1, a2);
         break;
     case INDEX_op_st_i32:
     case INDEX_op_st32_i64:
-        tcg_out_ldst(s, MO_32, LDST_ST, REG0(0), a1, a2);
+        tcg_out_ldst(s, I3312_STRW, REG0(0), a1, a2);
         break;
     case INDEX_op_st_i64:
-        tcg_out_ldst(s, MO_64, LDST_ST, REG0(0), a1, a2);
+        tcg_out_ldst(s, I3312_STRX, REG0(0), a1, a2);
         break;
 
     case INDEX_op_add_i32:
-- 
1.9.0