[PATCH 01/10] target/i386: use cpu_cc_dst for CC_OP_POPCNT

Paolo Bonzini posted 10 patches 5 months, 1 week ago
Maintainers: Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Eduardo Habkost <eduardo@habkost.net>
[PATCH 01/10] target/i386: use cpu_cc_dst for CC_OP_POPCNT
Posted by Paolo Bonzini 5 months, 1 week ago
It is the only POPCNT that computes ZF from one of the cc_op_* registers,
but it uses cpu_cc_src instead of cpu_cc_dst like the others.  Do not
make it the odd one off.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/cpu.h           | 2 +-
 target/i386/tcg/cc_helper.c | 2 +-
 target/i386/tcg/translate.c | 2 +-
 target/i386/tcg/emit.c.inc  | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 7e2a9b56aea..f54cd93b3f9 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1332,7 +1332,7 @@ typedef enum {
     CC_OP_BMILGQ,
 
     CC_OP_CLR, /* Z set, all other flags clear.  */
-    CC_OP_POPCNT, /* Z via CC_SRC, all other flags clear.  */
+    CC_OP_POPCNT, /* Z via CC_DST, all other flags clear.  */
 
     CC_OP_NB,
 } CCOp;
diff --git a/target/i386/tcg/cc_helper.c b/target/i386/tcg/cc_helper.c
index f76e9cb8cfb..301ed954064 100644
--- a/target/i386/tcg/cc_helper.c
+++ b/target/i386/tcg/cc_helper.c
@@ -107,7 +107,7 @@ target_ulong helper_cc_compute_all(target_ulong dst, target_ulong src1,
     case CC_OP_CLR:
         return CC_Z | CC_P;
     case CC_OP_POPCNT:
-        return src1 ? 0 : CC_Z;
+        return dst ? 0 : CC_Z;
 
     case CC_OP_MULB:
         return compute_all_mulb(dst, src1);
diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index ad1819815ab..f32cda4e169 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -324,7 +324,7 @@ static const uint8_t cc_op_live[CC_OP_NB] = {
     [CC_OP_ADOX] = USES_CC_SRC | USES_CC_SRC2,
     [CC_OP_ADCOX] = USES_CC_DST | USES_CC_SRC | USES_CC_SRC2,
     [CC_OP_CLR] = 0,
-    [CC_OP_POPCNT] = USES_CC_SRC,
+    [CC_OP_POPCNT] = USES_CC_DST,
 };
 
 static void set_cc_op_1(DisasContext *s, CCOp op, bool dirty)
diff --git a/target/i386/tcg/emit.c.inc b/target/i386/tcg/emit.c.inc
index 11faa70b5e2..fc7477833bc 100644
--- a/target/i386/tcg/emit.c.inc
+++ b/target/i386/tcg/emit.c.inc
@@ -2804,10 +2804,10 @@ static void gen_POPA(DisasContext *s, X86DecodedInsn *decode)
 
 static void gen_POPCNT(DisasContext *s, X86DecodedInsn *decode)
 {
-    decode->cc_src = tcg_temp_new();
+    decode->cc_dst = tcg_temp_new();
     decode->cc_op = CC_OP_POPCNT;
 
-    tcg_gen_mov_tl(decode->cc_src, s->T0);
+    tcg_gen_mov_tl(decode->cc_dst, s->T0);
     tcg_gen_ctpop_tl(s->T0, s->T0);
 }
 
-- 
2.45.2
Re: [PATCH 01/10] target/i386: use cpu_cc_dst for CC_OP_POPCNT
Posted by Richard Henderson 5 months, 1 week ago
On 6/20/24 02:54, Paolo Bonzini wrote:
> It is the only POPCNT that computes ZF from one of the cc_op_* registers,
> but it uses cpu_cc_src instead of cpu_cc_dst like the others.  Do not
> make it the odd one off.
> 
> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
> ---
>   target/i386/cpu.h           | 2 +-
>   target/i386/tcg/cc_helper.c | 2 +-
>   target/i386/tcg/translate.c | 2 +-
>   target/i386/tcg/emit.c.inc  | 4 ++--
>   4 files changed, 5 insertions(+), 5 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~