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* [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG
@ 2008-10-25 19:59 Andreas Färber
  2008-10-25 20:09 ` Paul Brook
  0 siblings, 1 reply; 7+ messages in thread
From: Andreas Färber @ 2008-10-25 19:59 UTC (permalink / raw)
  To: qemu-devel; +Cc: Aurélien Jarno

[-- Attachment #1: Type: text/plain, Size: 3509 bytes --]

Replace op_405_check_satu with a conditional movi_tl.

Replace {op,do}_405_check_sat with inline TCG instructions.

Signed-off-by: Andreas Faerber <andreas.faerber@web.de>

---
  op_405_check_sat is what currently breaks on OSX/ppc with gcc4.
  With this patch applied, the next dyngen breakage is op_40x_rfci.

  Note that since this is a 405 instruction, it is only compile-tested.

  target-ppc/op.c        |   15 ---------------
  target-ppc/op_helper.c |   12 ------------
  target-ppc/translate.c |   31 +++++++++++++++++++++++++++----
  3 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/target-ppc/op.c b/target-ppc/op.c
index 2271ed0..1bb213b 100644
--- a/target-ppc/op.c
+++ b/target-ppc/op.c
@@ -1558,12 +1558,6 @@ void OPPROTO op_405_mullhwu (void)
      RETURN();
  }

-void OPPROTO op_405_check_sat (void)
-{
-    do_405_check_sat();
-    RETURN();
-}
-
  void OPPROTO op_405_check_ovu (void)
  {
      if (likely(T0 >= T2)) {
@@ -1574,15 +1568,6 @@ void OPPROTO op_405_check_ovu (void)
      RETURN();
  }

-void OPPROTO op_405_check_satu (void)
-{
-    if (unlikely(T0 < T2)) {
-        /* Saturate result */
-        T0 = UINT32_MAX;
-    }
-    RETURN();
-}
-
  void OPPROTO op_load_dcr (void)
  {
      do_load_dcr();
diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
index 32b3471..e78ba82 100644
--- a/target-ppc/op_helper.c
+++ b/target-ppc/op_helper.c
@@ -1729,18 +1729,6 @@ void do_op_602_mfrom (void)

  / 
*****************************************************************************/
  /* Embedded PowerPC specific helpers */
-void do_405_check_sat (void)
-{
-    if (!likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
-                !(((uint32_t)T0 ^ (uint32_t)T2) >> 31))) {
-        /* Saturate result */
-        if (T2 >> 31) {
-            T0 = INT32_MIN;
-        } else {
-            T0 = INT32_MAX;
-        }
-    }
-}

  /* XXX: to be improved to check access rights when in user-mode */
  void do_load_dcr (void)
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index 8f4591a..b3fc02c 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -5071,10 +5071,33 @@ static always_inline void gen_405_mulladd_insn  
(DisasContext *ctx,
      }
      if (opc3 & 0x02) {
          /* Saturate */
-        if (opc3 & 0x01)
-            gen_op_405_check_sat();
-        else
-            gen_op_405_check_satu();
+        int endLabel = gen_new_label();
+        if (opc3 & 0x01) {
+            TCGv tmp = tcg_temp_new(TCG_TYPE_TL);
+            tcg_gen_xor_tl(tmp, cpu_T[1], cpu_T[2]);
+            tcg_gen_shri_tl(tmp, tmp, 31);
+            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, endLabel);
+
+            tcg_gen_xor_tl(tmp, cpu_T[0], cpu_T[2]);
+            tcg_gen_shri_tl(tmp, tmp, 31);
+            tcg_gen_brcondi_tl(TCG_COND_NE, tmp, 0, endLabel);
+
+            int innerLabel = gen_new_label();
+            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
+            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, innerLabel);
+
+            tcg_gen_movi_tl(cpu_T[0], INT32_MIN);
+            tcg_gen_br(endLabel);
+
+            gen_set_label(innerLabel);
+            tcg_gen_movi_tl(cpu_T[0], INT32_MAX);
+
+            tcg_temp_free(tmp);
+        } else {
+            tcg_gen_brcond_tl(TCG_COND_GEU, cpu_T[0], cpu_T[2],  
endLabel);
+            tcg_gen_movi_tl(cpu_T[0], UINT32_MAX);
+        }
+        gen_set_label(endLabel);
      }
      tcg_gen_mov_tl(cpu_gpr[rt], cpu_T[0]);
      if (unlikely(Rc) != 0) {
-- 
1.5.6.5


[-- Attachment #2: op_405_check_sat.patch --]
[-- Type: application/octet-stream, Size: 3450 bytes --]

From 8846a0e54873ae1504a62fc064c6cd53dde9c04d Mon Sep 17 00:00:00 2001
From: =?utf-8?q?Andreas=20F=C3=A4rber?= <andreas.faerber@web.de>
Date: Sat, 25 Oct 2008 21:41:15 +0200
Subject: [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG

---
 target-ppc/op.c        |   15 ---------------
 target-ppc/op_helper.c |   12 ------------
 target-ppc/translate.c |   31 +++++++++++++++++++++++++++----
 3 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/target-ppc/op.c b/target-ppc/op.c
index 2271ed0..1bb213b 100644
--- a/target-ppc/op.c
+++ b/target-ppc/op.c
@@ -1558,12 +1558,6 @@ void OPPROTO op_405_mullhwu (void)
     RETURN();
 }
 
-void OPPROTO op_405_check_sat (void)
-{
-    do_405_check_sat();
-    RETURN();
-}
-
 void OPPROTO op_405_check_ovu (void)
 {
     if (likely(T0 >= T2)) {
@@ -1574,15 +1568,6 @@ void OPPROTO op_405_check_ovu (void)
     RETURN();
 }
 
-void OPPROTO op_405_check_satu (void)
-{
-    if (unlikely(T0 < T2)) {
-        /* Saturate result */
-        T0 = UINT32_MAX;
-    }
-    RETURN();
-}
-
 void OPPROTO op_load_dcr (void)
 {
     do_load_dcr();
diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
index 32b3471..e78ba82 100644
--- a/target-ppc/op_helper.c
+++ b/target-ppc/op_helper.c
@@ -1729,18 +1729,6 @@ void do_op_602_mfrom (void)
 
 /*****************************************************************************/
 /* Embedded PowerPC specific helpers */
-void do_405_check_sat (void)
-{
-    if (!likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
-                !(((uint32_t)T0 ^ (uint32_t)T2) >> 31))) {
-        /* Saturate result */
-        if (T2 >> 31) {
-            T0 = INT32_MIN;
-        } else {
-            T0 = INT32_MAX;
-        }
-    }
-}
 
 /* XXX: to be improved to check access rights when in user-mode */
 void do_load_dcr (void)
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index 8f4591a..b3fc02c 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -5071,10 +5071,33 @@ static always_inline void gen_405_mulladd_insn (DisasContext *ctx,
     }
     if (opc3 & 0x02) {
         /* Saturate */
-        if (opc3 & 0x01)
-            gen_op_405_check_sat();
-        else
-            gen_op_405_check_satu();
+        int endLabel = gen_new_label();
+        if (opc3 & 0x01) {
+            TCGv tmp = tcg_temp_new(TCG_TYPE_TL);
+            tcg_gen_xor_tl(tmp, cpu_T[1], cpu_T[2]);
+            tcg_gen_shri_tl(tmp, tmp, 31);
+            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, endLabel);
+
+            tcg_gen_xor_tl(tmp, cpu_T[0], cpu_T[2]);
+            tcg_gen_shri_tl(tmp, tmp, 31);
+            tcg_gen_brcondi_tl(TCG_COND_NE, tmp, 0, endLabel);
+
+            int innerLabel = gen_new_label();
+            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
+            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, innerLabel);
+
+            tcg_gen_movi_tl(cpu_T[0], INT32_MIN);
+            tcg_gen_br(endLabel);
+
+            gen_set_label(innerLabel);
+            tcg_gen_movi_tl(cpu_T[0], INT32_MAX);
+
+            tcg_temp_free(tmp);
+        } else {
+            tcg_gen_brcond_tl(TCG_COND_GEU, cpu_T[0], cpu_T[2], endLabel);
+            tcg_gen_movi_tl(cpu_T[0], UINT32_MAX);
+        }
+        gen_set_label(endLabel);
     }
     tcg_gen_mov_tl(cpu_gpr[rt], cpu_T[0]);
     if (unlikely(Rc) != 0) {
-- 
1.5.6.5


^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG
  2008-10-25 19:59 [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG Andreas Färber
@ 2008-10-25 20:09 ` Paul Brook
  2008-10-25 20:25   ` Andreas Färber
  2008-10-28 20:01   ` [Qemu-devel] [PATCH v2] " Andreas Färber
  0 siblings, 2 replies; 7+ messages in thread
From: Paul Brook @ 2008-10-25 20:09 UTC (permalink / raw)
  To: qemu-devel; +Cc: Andreas Färber, Aurélien Jarno

On Saturday 25 October 2008, Andreas Färber wrote:
> +            tcg_gen_shri_tl(tmp, tmp, 31);
> +            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, endLabel);

Is this really right for ppc64?
You can easily test the high bit using TCG_COND_LT.

> +            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
> +            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, innerLabel);
> +
> +            tcg_gen_movi_tl(cpu_T[0], INT32_MIN);
> +            tcg_gen_br(endLabel);
> +
> +            gen_set_label(innerLabel);
> +            tcg_gen_movi_tl(cpu_T[0], INT32_MAX);

((signed)x >> 31) ^ 0x7fffffff)
is a much more efficient way of implementing this.

Paul

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG
  2008-10-25 20:09 ` Paul Brook
@ 2008-10-25 20:25   ` Andreas Färber
  2008-10-25 23:29     ` Anthony Liguori
  2008-10-28 20:01   ` [Qemu-devel] [PATCH v2] " Andreas Färber
  1 sibling, 1 reply; 7+ messages in thread
From: Andreas Färber @ 2008-10-25 20:25 UTC (permalink / raw)
  To: Paul Brook; +Cc: qemu-devel, Aurélien Jarno


Am 25.10.2008 um 22:09 schrieb Paul Brook:

> On Saturday 25 October 2008, Andreas Färber wrote:
>> +            tcg_gen_shri_tl(tmp, tmp, 31);
>> +            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, endLabel);
>
> Is this really right for ppc64?

http://en.wikipedia.org/wiki/PowerPC_400
says the embedded 400 family is 32-bit.

> You can easily test the high bit using TCG_COND_LT.
>
>> +            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
>> +            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, innerLabel);
>> +
>> +            tcg_gen_movi_tl(cpu_T[0], INT32_MIN);
>> +            tcg_gen_br(endLabel);
>> +
>> +            gen_set_label(innerLabel);
>> +            tcg_gen_movi_tl(cpu_T[0], INT32_MAX);
>
> ((signed)x >> 31) ^ 0x7fffffff)
> is a much more efficient way of implementing this.

I just translated the original code that's being removed in the  
patch. ;)

On second thoughts I am wondering whether we should use a new helper  
here instead of TCG instructions? (The Readme mentions 20 instructions  
as limit.) Unfortunately I wouldn't know how to yet, it doesn't work  
simply calling the old helper, e.g., tcg_gen_helper_0_0(do_40x_rfci);  
because the function name is unknown there.

Andreas

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG
  2008-10-25 20:25   ` Andreas Färber
@ 2008-10-25 23:29     ` Anthony Liguori
  2008-10-27 16:05       ` Hollis Blanchard
  0 siblings, 1 reply; 7+ messages in thread
From: Anthony Liguori @ 2008-10-25 23:29 UTC (permalink / raw)
  To: qemu-devel; +Cc: Hollis Blanchard, Paul Brook, Aurélien Jarno

Andreas Färber wrote:
>
> Am 25.10.2008 um 22:09 schrieb Paul Brook:
>
>> On Saturday 25 October 2008, Andreas Färber wrote:
>>> +            tcg_gen_shri_tl(tmp, tmp, 31);
>>> +            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, endLabel);
>>
>> Is this really right for ppc64?
>
> http://en.wikipedia.org/wiki/PowerPC_400
> says the embedded 400 family is 32-bit.

I'm pretty sure it is.  Hollis?

Regards,

Anthony Liguori

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG
  2008-10-25 23:29     ` Anthony Liguori
@ 2008-10-27 16:05       ` Hollis Blanchard
  0 siblings, 0 replies; 7+ messages in thread
From: Hollis Blanchard @ 2008-10-27 16:05 UTC (permalink / raw)
  To: Anthony Liguori; +Cc: qemu-devel, Aurélien Jarno, Paul Brook

On Sat, 2008-10-25 at 18:29 -0500, Anthony Liguori wrote:
> Andreas Färber wrote:
> >
> > Am 25.10.2008 um 22:09 schrieb Paul Brook:
> >
> >> On Saturday 25 October 2008, Andreas Färber wrote:
> >>> +            tcg_gen_shri_tl(tmp, tmp, 31);
> >>> +            tcg_gen_brcondi_tl(TCG_COND_EQ, tmp, 0, endLabel);
> >>
> >> Is this really right for ppc64?
> >
> > http://en.wikipedia.org/wiki/PowerPC_400
> > says the embedded 400 family is 32-bit.
> 
> I'm pretty sure it is.  Hollis?

It is.

-- 
Hollis Blanchard
IBM Linux Technology Center

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Qemu-devel] [PATCH v2] ppc: Convert op_405_check_{sat,satu} to TCG
  2008-10-25 20:09 ` Paul Brook
  2008-10-25 20:25   ` Andreas Färber
@ 2008-10-28 20:01   ` Andreas Färber
  2008-11-01  0:55     ` Aurélien Jarno
  1 sibling, 1 reply; 7+ messages in thread
From: Andreas Färber @ 2008-10-28 20:01 UTC (permalink / raw)
  To: qemu-devel; +Cc: Paul Brook, Aurélien Jarno

[-- Attachment #1: Type: text/plain, Size: 3100 bytes --]

Replace op_405_check_satu with a conditional movi_tl.

Replace {op,do}_405_check_sat with inline TCG instructions.

Signed-off-by: Andreas Faerber <andreas.faerber@web.de>
---
  Updated with simplifications suggested by Paul Brook.
  Still only compile-tested - please verify whether I got the logic  
right.

  target-ppc/op.c        |   15 ---------------
  target-ppc/op_helper.c |   12 ------------
  target-ppc/translate.c |   22 ++++++++++++++++++----
  3 files changed, 18 insertions(+), 31 deletions(-)

diff --git a/target-ppc/op.c b/target-ppc/op.c
index bcdb11d..f9b1910 100644
--- a/target-ppc/op.c
+++ b/target-ppc/op.c
@@ -1502,12 +1502,6 @@ void OPPROTO op_405_mullhwu (void)
      RETURN();
  }

-void OPPROTO op_405_check_sat (void)
-{
-    do_405_check_sat();
-    RETURN();
-}
-
  void OPPROTO op_405_check_ovu (void)
  {
      if (likely(T0 >= T2)) {
@@ -1518,15 +1512,6 @@ void OPPROTO op_405_check_ovu (void)
      RETURN();
  }

-void OPPROTO op_405_check_satu (void)
-{
-    if (unlikely(T0 < T2)) {
-        /* Saturate result */
-        T0 = UINT32_MAX;
-    }
-    RETURN();
-}
-
  void OPPROTO op_load_dcr (void)
  {
      do_load_dcr();
diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
index 32b3471..e78ba82 100644
--- a/target-ppc/op_helper.c
+++ b/target-ppc/op_helper.c
@@ -1729,18 +1729,6 @@ void do_op_602_mfrom (void)

  / 
*****************************************************************************/
  /* Embedded PowerPC specific helpers */
-void do_405_check_sat (void)
-{
-    if (!likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
-                !(((uint32_t)T0 ^ (uint32_t)T2) >> 31))) {
-        /* Saturate result */
-        if (T2 >> 31) {
-            T0 = INT32_MIN;
-        } else {
-            T0 = INT32_MAX;
-        }
-    }
-}

  /* XXX: to be improved to check access rights when in user-mode */
  void do_load_dcr (void)
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index a977ea4..2a4a70d 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -5106,10 +5106,24 @@ static always_inline void gen_405_mulladd_insn  
(DisasContext *ctx,
      }
      if (opc3 & 0x02) {
          /* Saturate */
-        if (opc3 & 0x01)
-            gen_op_405_check_sat();
-        else
-            gen_op_405_check_satu();
+        int endLabel = gen_new_label();
+        if (opc3 & 0x01) {
+            TCGv tmp = tcg_temp_new(TCG_TYPE_TL);
+            tcg_gen_xor_tl(tmp, cpu_T[1], cpu_T[2]);
+            tcg_gen_brcondi_tl(TCG_COND_GE, tmp, 0, endLabel);
+
+            tcg_gen_xor_tl(tmp, cpu_T[0], cpu_T[2]);
+            tcg_gen_brcondi_tl(TCG_COND_LT, tmp, 0, endLabel);
+
+            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
+            tcg_gen_xori_tl(cpu_T[0], tmp, 0x7fffffff);
+
+            tcg_temp_free(tmp);
+        } else {
+            tcg_gen_brcond_tl(TCG_COND_GEU, cpu_T[0], cpu_T[2],  
endLabel);
+            tcg_gen_movi_tl(cpu_T[0], UINT32_MAX);
+        }
+        gen_set_label(endLabel);
      }
      tcg_gen_mov_tl(cpu_gpr[rt], cpu_T[0]);
      if (unlikely(Rc) != 0) {
-- 
1.5.6.5


[-- Attachment #2: op_405_check_sat.patch --]
[-- Type: application/octet-stream, Size: 3107 bytes --]

From 439fab33c937e05d271e5e7bd6731e799ff4d97b Mon Sep 17 00:00:00 2001
From: =?utf-8?q?Andreas=20F=C3=A4rber?= <andreas.faerber@web.de>
Date: Tue, 28 Oct 2008 20:51:50 +0100
Subject: [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG

---
 target-ppc/op.c        |   15 ---------------
 target-ppc/op_helper.c |   12 ------------
 target-ppc/translate.c |   22 ++++++++++++++++++----
 3 files changed, 18 insertions(+), 31 deletions(-)

diff --git a/target-ppc/op.c b/target-ppc/op.c
index bcdb11d..f9b1910 100644
--- a/target-ppc/op.c
+++ b/target-ppc/op.c
@@ -1502,12 +1502,6 @@ void OPPROTO op_405_mullhwu (void)
     RETURN();
 }
 
-void OPPROTO op_405_check_sat (void)
-{
-    do_405_check_sat();
-    RETURN();
-}
-
 void OPPROTO op_405_check_ovu (void)
 {
     if (likely(T0 >= T2)) {
@@ -1518,15 +1512,6 @@ void OPPROTO op_405_check_ovu (void)
     RETURN();
 }
 
-void OPPROTO op_405_check_satu (void)
-{
-    if (unlikely(T0 < T2)) {
-        /* Saturate result */
-        T0 = UINT32_MAX;
-    }
-    RETURN();
-}
-
 void OPPROTO op_load_dcr (void)
 {
     do_load_dcr();
diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
index 32b3471..e78ba82 100644
--- a/target-ppc/op_helper.c
+++ b/target-ppc/op_helper.c
@@ -1729,18 +1729,6 @@ void do_op_602_mfrom (void)
 
 /*****************************************************************************/
 /* Embedded PowerPC specific helpers */
-void do_405_check_sat (void)
-{
-    if (!likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
-                !(((uint32_t)T0 ^ (uint32_t)T2) >> 31))) {
-        /* Saturate result */
-        if (T2 >> 31) {
-            T0 = INT32_MIN;
-        } else {
-            T0 = INT32_MAX;
-        }
-    }
-}
 
 /* XXX: to be improved to check access rights when in user-mode */
 void do_load_dcr (void)
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index a977ea4..2a4a70d 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -5106,10 +5106,24 @@ static always_inline void gen_405_mulladd_insn (DisasContext *ctx,
     }
     if (opc3 & 0x02) {
         /* Saturate */
-        if (opc3 & 0x01)
-            gen_op_405_check_sat();
-        else
-            gen_op_405_check_satu();
+        int endLabel = gen_new_label();
+        if (opc3 & 0x01) {
+            TCGv tmp = tcg_temp_new(TCG_TYPE_TL);
+            tcg_gen_xor_tl(tmp, cpu_T[1], cpu_T[2]);
+            tcg_gen_brcondi_tl(TCG_COND_GE, tmp, 0, endLabel);
+
+            tcg_gen_xor_tl(tmp, cpu_T[0], cpu_T[2]);
+            tcg_gen_brcondi_tl(TCG_COND_LT, tmp, 0, endLabel);
+
+            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
+            tcg_gen_xori_tl(cpu_T[0], tmp, 0x7fffffff);
+
+            tcg_temp_free(tmp);
+        } else {
+            tcg_gen_brcond_tl(TCG_COND_GEU, cpu_T[0], cpu_T[2], endLabel);
+            tcg_gen_movi_tl(cpu_T[0], UINT32_MAX);
+        }
+        gen_set_label(endLabel);
     }
     tcg_gen_mov_tl(cpu_gpr[rt], cpu_T[0]);
     if (unlikely(Rc) != 0) {
-- 
1.5.6.5


[-- Attachment #3: Type: text/plain, Size: 1 bytes --]



^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Re: [Qemu-devel] [PATCH v2] ppc: Convert op_405_check_{sat,satu} to TCG
  2008-10-28 20:01   ` [Qemu-devel] [PATCH v2] " Andreas Färber
@ 2008-11-01  0:55     ` Aurélien Jarno
  0 siblings, 0 replies; 7+ messages in thread
From: Aurélien Jarno @ 2008-11-01  0:55 UTC (permalink / raw)
  To: Andreas Färber; +Cc: qemu-devel

On Tue, Oct 28, 2008 at 09:01:39PM +0100, Andreas Färber wrote:
> Replace op_405_check_satu with a conditional movi_tl.
>
> Replace {op,do}_405_check_sat with inline TCG instructions.

Thanks, I applied it as part of commit 5591, "target-ppc: convert 405
MAC instructions to TCG"

> Signed-off-by: Andreas Faerber <andreas.faerber@web.de>
> ---
>  Updated with simplifications suggested by Paul Brook.
>  Still only compile-tested - please verify whether I got the logic  
> right.
>
>  target-ppc/op.c        |   15 ---------------
>  target-ppc/op_helper.c |   12 ------------
>  target-ppc/translate.c |   22 ++++++++++++++++++----
>  3 files changed, 18 insertions(+), 31 deletions(-)
>
> diff --git a/target-ppc/op.c b/target-ppc/op.c
> index bcdb11d..f9b1910 100644
> --- a/target-ppc/op.c
> +++ b/target-ppc/op.c
> @@ -1502,12 +1502,6 @@ void OPPROTO op_405_mullhwu (void)
>      RETURN();
>  }
>
> -void OPPROTO op_405_check_sat (void)
> -{
> -    do_405_check_sat();
> -    RETURN();
> -}
> -
>  void OPPROTO op_405_check_ovu (void)
>  {
>      if (likely(T0 >= T2)) {
> @@ -1518,15 +1512,6 @@ void OPPROTO op_405_check_ovu (void)
>      RETURN();
>  }
>
> -void OPPROTO op_405_check_satu (void)
> -{
> -    if (unlikely(T0 < T2)) {
> -        /* Saturate result */
> -        T0 = UINT32_MAX;
> -    }
> -    RETURN();
> -}
> -
>  void OPPROTO op_load_dcr (void)
>  {
>      do_load_dcr();
> diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
> index 32b3471..e78ba82 100644
> --- a/target-ppc/op_helper.c
> +++ b/target-ppc/op_helper.c
> @@ -1729,18 +1729,6 @@ void do_op_602_mfrom (void)
>
>  / 
> *****************************************************************************/
>  /* Embedded PowerPC specific helpers */
> -void do_405_check_sat (void)
> -{
> -    if (!likely((((uint32_t)T1 ^ (uint32_t)T2) >> 31) ||
> -                !(((uint32_t)T0 ^ (uint32_t)T2) >> 31))) {
> -        /* Saturate result */
> -        if (T2 >> 31) {
> -            T0 = INT32_MIN;
> -        } else {
> -            T0 = INT32_MAX;
> -        }
> -    }
> -}
>
>  /* XXX: to be improved to check access rights when in user-mode */
>  void do_load_dcr (void)
> diff --git a/target-ppc/translate.c b/target-ppc/translate.c
> index a977ea4..2a4a70d 100644
> --- a/target-ppc/translate.c
> +++ b/target-ppc/translate.c
> @@ -5106,10 +5106,24 @@ static always_inline void gen_405_mulladd_insn  
> (DisasContext *ctx,
>      }
>      if (opc3 & 0x02) {
>          /* Saturate */
> -        if (opc3 & 0x01)
> -            gen_op_405_check_sat();
> -        else
> -            gen_op_405_check_satu();
> +        int endLabel = gen_new_label();
> +        if (opc3 & 0x01) {
> +            TCGv tmp = tcg_temp_new(TCG_TYPE_TL);
> +            tcg_gen_xor_tl(tmp, cpu_T[1], cpu_T[2]);
> +            tcg_gen_brcondi_tl(TCG_COND_GE, tmp, 0, endLabel);
> +
> +            tcg_gen_xor_tl(tmp, cpu_T[0], cpu_T[2]);
> +            tcg_gen_brcondi_tl(TCG_COND_LT, tmp, 0, endLabel);
> +
> +            tcg_gen_shri_tl(tmp, cpu_T[2], 31);
> +            tcg_gen_xori_tl(cpu_T[0], tmp, 0x7fffffff);
> +
> +            tcg_temp_free(tmp);
> +        } else {
> +            tcg_gen_brcond_tl(TCG_COND_GEU, cpu_T[0], cpu_T[2],  
> endLabel);
> +            tcg_gen_movi_tl(cpu_T[0], UINT32_MAX);
> +        }
> +        gen_set_label(endLabel);
>      }
>      tcg_gen_mov_tl(cpu_gpr[rt], cpu_T[0]);
>      if (unlikely(Rc) != 0) {
> -- 
> 1.5.6.5
>


>


-- 
  .''`.  Aurelien Jarno	            | GPG: 1024D/F1BCDB73
 : :' :  Debian developer           | Electrical Engineer
 `. `'   aurel32@debian.org         | aurelien@aurel32.net
   `-    people.debian.org/~aurel32 | www.aurel32.net

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2008-11-01  0:55 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-10-25 19:59 [Qemu-devel] [PATCH] ppc: Convert op_405_check_{sat,satu} to TCG Andreas Färber
2008-10-25 20:09 ` Paul Brook
2008-10-25 20:25   ` Andreas Färber
2008-10-25 23:29     ` Anthony Liguori
2008-10-27 16:05       ` Hollis Blanchard
2008-10-28 20:01   ` [Qemu-devel] [PATCH v2] " Andreas Färber
2008-11-01  0:55     ` Aurélien Jarno

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