target/m68k: Avoid tcg_const_i32 in bfop_reg

Tidy up the whole function, hoisting is_bfffo as a common test
for whether tlen and tofs needed. Use tcg_constant_i32, and load
a separate temporary for mask.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 20 insertions, 22 deletions

diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index 0002d80bf9..e78722fba8 100644
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -4027,14 +4027,8 @@ DISAS_INSN(bfop_reg)
     TCGv src = DREG(insn, 0);
     int len = ((extract32(ext, 0, 5) - 1) & 31) + 1;
     int ofs = extract32(ext, 6, 5);  /* big bit-endian */
-    TCGv mask, tofs, tlen;
-
-    tofs = NULL;
-    tlen = NULL;
-    if ((insn & 0x0f00) == 0x0d00) { /* bfffo */
-        tofs = tcg_temp_new();
-        tlen = tcg_temp_new();
-    }
+    TCGv mask, tofs = NULL, tlen = NULL;
+    bool is_bfffo = (insn & 0x0f00) == 0x0d00;
 
     if ((ext & 0x820) == 0) {
         /* Immediate width and offset.  */
@@ -4045,45 +4039,49 @@ DISAS_INSN(bfop_reg)
             tcg_gen_rotli_i32(QREG_CC_N, src, ofs);
         }
         tcg_gen_andi_i32(QREG_CC_N, QREG_CC_N, ~maski);
-        mask = tcg_const_i32(ror32(maski, ofs));
-        if (tofs) {
-            tcg_gen_movi_i32(tofs, ofs);
-            tcg_gen_movi_i32(tlen, len);
+
+        mask = tcg_constant_i32(ror32(maski, ofs));
+        if (is_bfffo) {
+            tofs = tcg_constant_i32(ofs);
+            tlen = tcg_constant_i32(len);
         }
     } else {
         TCGv tmp = tcg_temp_new();
+
+        mask = tcg_temp_new();
         if (ext & 0x20) {
             /* Variable width */
             tcg_gen_subi_i32(tmp, DREG(ext, 0), 1);
             tcg_gen_andi_i32(tmp, tmp, 31);
-            mask = tcg_const_i32(0x7fffffffu);
-            tcg_gen_shr_i32(mask, mask, tmp);
-            if (tlen) {
+            tcg_gen_shr_i32(mask, tcg_constant_i32(0x7fffffffu), tmp);
+            if (is_bfffo) {
+                tlen = tcg_temp_new();
                 tcg_gen_addi_i32(tlen, tmp, 1);
             }
         } else {
             /* Immediate width */
-            mask = tcg_const_i32(0x7fffffffu >> (len - 1));
-            if (tlen) {
-                tcg_gen_movi_i32(tlen, len);
+            tcg_gen_movi_i32(mask, 0x7fffffffu >> (len - 1));
+            if (is_bfffo) {
+                tlen = tcg_constant_i32(len);
             }
         }
+
         if (ext & 0x800) {
             /* Variable offset */
             tcg_gen_andi_i32(tmp, DREG(ext, 6), 31);
             tcg_gen_rotl_i32(QREG_CC_N, src, tmp);
             tcg_gen_andc_i32(QREG_CC_N, QREG_CC_N, mask);
             tcg_gen_rotr_i32(mask, mask, tmp);
-            if (tofs) {
-                tcg_gen_mov_i32(tofs, tmp);
+            if (is_bfffo) {
+                tofs = tmp;
             }
         } else {
             /* Immediate offset (and variable width) */
             tcg_gen_rotli_i32(QREG_CC_N, src, ofs);
             tcg_gen_andc_i32(QREG_CC_N, QREG_CC_N, mask);
             tcg_gen_rotri_i32(mask, mask, ofs);
-            if (tofs) {
-                tcg_gen_movi_i32(tofs, ofs);
+            if (is_bfffo) {
+                tofs = tcg_constant_i32(ofs);
             }
         }
     }