[PATCH v2 14/35] tcg/i386: Support TCG_COND_TST{EQ,NE}

Richard Henderson posted 35 patches 1 year, 1 month ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, Laurent Vivier <laurent@vivier.eu>, WANG Xuerui <git@xen0n.name>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Aurelien Jarno <aurelien@aurel32.net>, Huacai Chen <chenhuacai@kernel.org>, Jiaxun Yang <jiaxun.yang@flygoat.com>, Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>, Palmer Dabbelt <palmer@dabbelt.com>, Alistair Francis <Alistair.Francis@wdc.com>, Stefan Weil <sw@weilnetz.de>
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[PATCH v2 14/35] tcg/i386: Support TCG_COND_TST{EQ,NE}
Posted by Richard Henderson 1 year, 1 month ago
Merge tcg_out_testi into tcg_out_cmp and adjust the two uses.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/i386/tcg-target.c.inc | 83 ++++++++++++++++++++++-----------------
 1 file changed, 47 insertions(+), 36 deletions(-)

diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc
index 7d5ed0d045..17b250f16f 100644
--- a/tcg/i386/tcg-target.c.inc
+++ b/tcg/i386/tcg-target.c.inc
@@ -505,6 +505,8 @@ static const uint8_t tcg_cond_to_jcc[] = {
     [TCG_COND_GEU] = JCC_JAE,
     [TCG_COND_LEU] = JCC_JBE,
     [TCG_COND_GTU] = JCC_JA,
+    [TCG_COND_TSTEQ] = JCC_JE,
+    [TCG_COND_TSTNE] = JCC_JNE,
 };
 
 #if TCG_TARGET_REG_BITS == 64
@@ -1422,15 +1424,35 @@ static void tcg_out_jxx(TCGContext *s, int opc, TCGLabel *l, bool small)
 static int tcg_out_cmp(TCGContext *s, TCGCond cond, TCGArg arg1,
                        TCGArg arg2, int const_arg2, int rexw)
 {
-    if (const_arg2) {
-        if (arg2 == 0) {
-            /* test r, r */
-            tcg_out_modrm(s, OPC_TESTL + rexw, arg1, arg1);
+    if (is_tst_cond(cond)) {
+        if (!const_arg2) {
+            tcg_out_modrm(s, OPC_TESTL + rexw, arg1, arg2);
+        } else if (arg2 <= 0xff && (TCG_TARGET_REG_BITS == 64 || arg1 < 4)) {
+            tcg_out_modrm(s, OPC_GRP3_Eb | P_REXB_RM, EXT3_TESTi, arg1);
+            tcg_out8(s, arg2);
+        } else if ((arg2 & ~0xff00) == 0 && arg1 < 4) {
+            tcg_out_modrm(s, OPC_GRP3_Eb, EXT3_TESTi, arg1 + 4);
+            tcg_out8(s, arg2 >> 8);
         } else {
-            tgen_arithi(s, ARITH_CMP + rexw, arg1, arg2, 0);
+            if (rexw) {
+                if (arg2 == (uint32_t)arg2) {
+                    rexw = 0;
+                } else {
+                    tcg_debug_assert(arg2 == (int32_t)arg2);
+                }
+            }
+            tcg_out_modrm(s, OPC_GRP3_Ev + rexw, EXT3_TESTi, arg1);
+            tcg_out32(s, arg2);
         }
     } else {
-        tgen_arithr(s, ARITH_CMP + rexw, arg1, arg2);
+        if (!const_arg2) {
+            tgen_arithr(s, ARITH_CMP + rexw, arg1, arg2);
+        } else if (arg2 == 0) {
+            tcg_out_modrm(s, OPC_TESTL + rexw, arg1, arg1);
+        } else {
+            tcg_debug_assert(!rexw || arg2 == (int32_t)arg2);
+            tgen_arithi(s, ARITH_CMP + rexw, arg1, arg2, 0);
+        }
     }
     return tcg_cond_to_jcc[cond];
 }
@@ -1449,18 +1471,21 @@ static void tcg_out_brcond2(TCGContext *s, const TCGArg *args,
 {
     TCGLabel *label_next = gen_new_label();
     TCGLabel *label_this = arg_label(args[5]);
+    TCGCond cond = args[4];
 
-    switch(args[4]) {
+    switch (cond) {
     case TCG_COND_EQ:
-        tcg_out_brcond(s, 0, TCG_COND_NE, args[0], args[2], const_args[2],
-                       label_next, 1);
-        tcg_out_brcond(s, 0, TCG_COND_EQ, args[1], args[3], const_args[3],
+    case TCG_COND_TSTEQ:
+        tcg_out_brcond(s, 0, tcg_invert_cond(cond),
+                       args[0], args[2], const_args[2], label_next, 1);
+        tcg_out_brcond(s, 0, cond, args[1], args[3], const_args[3],
                        label_this, small);
         break;
     case TCG_COND_NE:
-        tcg_out_brcond(s, 0, TCG_COND_NE, args[0], args[2], const_args[2],
+    case TCG_COND_TSTNE:
+        tcg_out_brcond(s, 0, cond, args[0], args[2], const_args[2],
                        label_this, small);
-        tcg_out_brcond(s, 0, TCG_COND_NE, args[1], args[3], const_args[3],
+        tcg_out_brcond(s, 0, cond, args[1], args[3], const_args[3],
                        label_this, small);
         break;
     case TCG_COND_LT:
@@ -1797,23 +1822,6 @@ static void tcg_out_nopn(TCGContext *s, int n)
     tcg_out8(s, 0x90);
 }
 
-/* Test register R vs immediate bits I, setting Z flag for EQ/NE. */
-static void __attribute__((unused))
-tcg_out_testi(TCGContext *s, TCGReg r, uint32_t i)
-{
-    /*
-     * This is used for testing alignment, so we can usually use testb.
-     * For i686, we have to use testl for %esi/%edi.
-     */
-    if (i <= 0xff && (TCG_TARGET_REG_BITS == 64 || r < 4)) {
-        tcg_out_modrm(s, OPC_GRP3_Eb | P_REXB_RM, EXT3_TESTi, r);
-        tcg_out8(s, i);
-    } else {
-        tcg_out_modrm(s, OPC_GRP3_Ev, EXT3_TESTi, r);
-        tcg_out32(s, i);
-    }
-}
-
 typedef struct {
     TCGReg base;
     int index;
@@ -2074,16 +2082,17 @@ static TCGLabelQemuLdst *prepare_host_addr(TCGContext *s, HostAddress *h,
         tcg_out_ld(s, TCG_TYPE_PTR, TCG_REG_L0, TCG_REG_L0,
                    offsetof(CPUTLBEntry, addend));
     } else if (a_mask) {
-        ldst = new_ldst_label(s);
+        int jcc;
 
+        ldst = new_ldst_label(s);
         ldst->is_ld = is_ld;
         ldst->oi = oi;
         ldst->addrlo_reg = addrlo;
         ldst->addrhi_reg = addrhi;
 
-        tcg_out_testi(s, addrlo, a_mask);
         /* jne slow_path */
-        tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0);
+        jcc = tcg_out_cmp(s, TCG_COND_TSTNE, addrlo, a_mask, true, false);
+        tcg_out_opc(s, OPC_JCC_long + jcc, 0, 0, 0);
         ldst->label_ptr[0] = s->code_ptr;
         s->code_ptr += 4;
     }
@@ -2229,9 +2238,10 @@ static void tcg_out_qemu_ld_direct(TCGContext *s, TCGReg datalo, TCGReg datahi,
         } else {
             TCGLabel *l1 = gen_new_label();
             TCGLabel *l2 = gen_new_label();
+            int jcc;
 
-            tcg_out_testi(s, h.base, 15);
-            tcg_out_jxx(s, JCC_JNE, l1, true);
+            jcc = tcg_out_cmp(s, TCG_COND_TSTNE, h.base, 15, true, false);
+            tcg_out_jxx(s, jcc, l1, true);
 
             tcg_out_vex_modrm_sib_offset(s, OPC_MOVDQA_VxWx + h.seg,
                                          TCG_TMP_VEC, 0,
@@ -2357,9 +2367,10 @@ static void tcg_out_qemu_st_direct(TCGContext *s, TCGReg datalo, TCGReg datahi,
         } else {
             TCGLabel *l1 = gen_new_label();
             TCGLabel *l2 = gen_new_label();
+            int jcc;
 
-            tcg_out_testi(s, h.base, 15);
-            tcg_out_jxx(s, JCC_JNE, l1, true);
+            jcc = tcg_out_cmp(s, TCG_COND_TSTNE, h.base, 15, true, false);
+            tcg_out_jxx(s, jcc, l1, true);
 
             tcg_out_vex_modrm_sib_offset(s, OPC_MOVDQA_WxVx + h.seg,
                                          TCG_TMP_VEC, 0,
-- 
2.34.1
Re: [PATCH v2 14/35] tcg/i386: Support TCG_COND_TST{EQ,NE}
Posted by Philippe Mathieu-Daudé 1 year ago
On 28/10/23 21:45, Richard Henderson wrote:
> Merge tcg_out_testi into tcg_out_cmp and adjust the two uses.
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   tcg/i386/tcg-target.c.inc | 83 ++++++++++++++++++++++-----------------
>   1 file changed, 47 insertions(+), 36 deletions(-)


>   #if TCG_TARGET_REG_BITS == 64
> @@ -1422,15 +1424,35 @@ static void tcg_out_jxx(TCGContext *s, int opc, TCGLabel *l, bool small)
>   static int tcg_out_cmp(TCGContext *s, TCGCond cond, TCGArg arg1,
>                          TCGArg arg2, int const_arg2, int rexw)
>   {
> -    if (const_arg2) {
> -        if (arg2 == 0) {
> -            /* test r, r */
> -            tcg_out_modrm(s, OPC_TESTL + rexw, arg1, arg1);
> +    if (is_tst_cond(cond)) {
> +        if (!const_arg2) {
> +            tcg_out_modrm(s, OPC_TESTL + rexw, arg1, arg2);
> +        } else if (arg2 <= 0xff && (TCG_TARGET_REG_BITS == 64 || arg1 < 4)) {
> +            tcg_out_modrm(s, OPC_GRP3_Eb | P_REXB_RM, EXT3_TESTi, arg1);
> +            tcg_out8(s, arg2);
> +        } else if ((arg2 & ~0xff00) == 0 && arg1 < 4) {
> +            tcg_out_modrm(s, OPC_GRP3_Eb, EXT3_TESTi, arg1 + 4);
> +            tcg_out8(s, arg2 >> 8);
>           } else {

For this part, a double-review from x86 developer is welcomed,

> -            tgen_arithi(s, ARITH_CMP + rexw, arg1, arg2, 0);
> +            if (rexw) {
> +                if (arg2 == (uint32_t)arg2) {
> +                    rexw = 0;
> +                } else {
> +                    tcg_debug_assert(arg2 == (int32_t)arg2);
> +                }
> +            }
> +            tcg_out_modrm(s, OPC_GRP3_Ev + rexw, EXT3_TESTi, arg1);
> +            tcg_out32(s, arg2);
>           }
>       } else {

then the rest is OK.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>