BSR/BSF TCG conversion

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4477 c046a42c-6fe2-441c-8c8c-71466251a162

BSR/BSF TCG conversion
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4477 c046a42c-6fe2-441c-8c8c-71466251a162
bellard
1 parent 7c6ce4ba
Showing 4 changed files with 54 additions and 72 deletions
target-i386/helper.c
target-i386/helper.h
target-i386/ops_template.h
target-i386/translate.c
@@ -5240,6 +5240,37 @@ void helper_movq(uint64_t *d, uint64_t *s)
  
 #endif
  
+/* bit operations */
+target_ulong helper_bsf(target_ulong t0)
+{
+    int count;
+    target_ulong res;
+
+    res = t0;
+    count = 0;
+    while ((res & 1) == 0) {
+        count++;
+        res >>= 1;
+    }
+    return count;
+}
+
+target_ulong helper_bsr(target_ulong t0)
+{
+    int count;
+    target_ulong res, mask;
+    
+    res = t0;
+    count = TARGET_LONG_BITS - 1;
+    mask = (target_ulong)1 << (TARGET_LONG_BITS - 1);
+    while ((res & mask) == 0) {
+        count--;
+        res <<= 1;
+    }
+    return count;
+}
+
+
 static int compute_all_eflags(void)
 {
     return CC_SRC;
@@ -187,6 +187,8 @@ void helper_fsave(target_ulong ptr, int data32);
 void helper_frstor(target_ulong ptr, int data32);
 void helper_fxsave(target_ulong ptr, int data64);
 void helper_fxrstor(target_ulong ptr, int data64);
+target_ulong helper_bsf(target_ulong t0);
+target_ulong helper_bsr(target_ulong t0);
  
 /* MMX/SSE */
  
@@ -200,51 +200,6 @@ void OPPROTO glue(op_setle_T0_sub, SUFFIX)(void)
     T0 = ((DATA_STYPE)src1 <= (DATA_STYPE)src2);
 }
  
-/* bit operations */
-#if DATA_BITS >= 16
-
-void OPPROTO glue(glue(op_bsf, SUFFIX), _T0_cc)(void)
-{
-    int count;
-    target_long res;
-
-    res = T0 & DATA_MASK;
-    if (res != 0) {
-        count = 0;
-        while ((res & 1) == 0) {
-            count++;
-            res >>= 1;
-        }
-        T1 = count;
-        CC_DST = 1; /* ZF = 0 */
-    } else {
-        CC_DST = 0; /* ZF = 1 */
-    }
-    FORCE_RET();
-}
-
-void OPPROTO glue(glue(op_bsr, SUFFIX), _T0_cc)(void)
-{
-    int count;
-    target_long res;
-
-    res = T0 & DATA_MASK;
-    if (res != 0) {
-        count = DATA_BITS - 1;
-        while ((res & SIGN_MASK) == 0) {
-            count--;
-            res <<= 1;
-        }
-        T1 = count;
-        CC_DST = 1; /* ZF = 0 */
-    } else {
-        CC_DST = 0; /* ZF = 1 */
-    }
-    FORCE_RET();
-}
-
-#endif
-
 /* string operations */
  
 void OPPROTO glue(op_movl_T0_Dshift, SUFFIX)(void)
@@ -498,23 +498,6 @@ static GenOpFunc *gen_op_cmov_reg_T1_T0[NB_OP_SIZES - 1][CPU_NB_REGS] = {
 #endif
 };
  
-static GenOpFunc *gen_op_bsx_T0_cc[3][2] = {
-    [0] = {
-        gen_op_bsfw_T0_cc,
-        gen_op_bsrw_T0_cc,
-    },
-    [1] = {
-        gen_op_bsfl_T0_cc,
-        gen_op_bsrl_T0_cc,
-    },
-#ifdef TARGET_X86_64
-    [2] = {
-        gen_op_bsfq_T0_cc,
-        gen_op_bsrq_T0_cc,
-    },
-#endif
-};
-
 static inline void gen_op_lds_T0_A0(int idx)
 {
     int mem_index = (idx >> 2) - 1;
@@ -5837,16 +5820,27 @@ static target_ulong disas_insn(DisasContext *s, target_ulong pc_start)
         break;
     case 0x1bc: /* bsf */
     case 0x1bd: /* bsr */
-        ot = dflag + OT_WORD;
-        modrm = ldub_code(s->pc++);
-        reg = ((modrm >> 3) & 7) | rex_r;
-        gen_ldst_modrm(s, modrm, ot, OR_TMP0, 0);
-        /* NOTE: in order to handle the 0 case, we must load the
-           result. It could be optimized with a generated jump */
-        gen_op_mov_TN_reg(ot, 1, reg);
-        gen_op_bsx_T0_cc[ot - OT_WORD][b & 1]();
-        gen_op_mov_reg_T1(ot, reg);
-        s->cc_op = CC_OP_LOGICB + ot;
+        {
+            int label1;
+            ot = dflag + OT_WORD;
+            modrm = ldub_code(s->pc++);
+            reg = ((modrm >> 3) & 7) | rex_r;
+            gen_ldst_modrm(s, modrm, ot, OR_TMP0, 0);
+            gen_extu(ot, cpu_T[0]);
+            label1 = gen_new_label();
+            tcg_gen_movi_tl(cpu_cc_dst, 0);
+            tcg_gen_brcond_tl(TCG_COND_EQ, cpu_T[0], tcg_const_tl(0), label1);
+            if (b & 1) {
+                tcg_gen_helper_1_1(helper_bsr, cpu_T[0], cpu_T[0]);
+            } else {
+                tcg_gen_helper_1_1(helper_bsf, cpu_T[0], cpu_T[0]);
+            }
+            gen_op_mov_reg_T0(ot, reg);
+            tcg_gen_movi_tl(cpu_cc_dst, 1);
+            gen_set_label(label1);
+            tcg_gen_discard_tl(cpu_cc_src);
+            s->cc_op = CC_OP_LOGICB + ot;
+        }
         break;
         /************************/
         /* bcd */