Patchwork [2/2] tcg/arm: Implement movcond_i32

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Submitter Peter Maydell
Date Sept. 26, 2012, 6:48 p.m.
Message ID <1348685335-16770-3-git-send-email-peter.maydell@linaro.org>
Download mbox | patch
Permalink /patch/187175/
State New
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Comments

Peter Maydell - Sept. 26, 2012, 6:48 p.m.
Implement movcond_i32 for ARM, as the sequence
  mov dst, v2   (implicitly done by the tcg common code)
  cmp c1, c2
  movCC dst, v1

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 tcg/arm/tcg-target.c |   10 ++++++++++
 tcg/arm/tcg-target.h |    2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)
Paolo Bonzini - Sept. 27, 2012, 6:33 a.m.
Il 26/09/2012 20:48, Peter Maydell ha scritto:
> Implement movcond_i32 for ARM, as the sequence
>   mov dst, v2   (implicitly done by the tcg common code)
>   cmp c1, c2
>   movCC dst, v1

Should you make tcg/optimize.c prefer "movcond a, a, b" to "movcond a,
b, a", similar to commit c2b0e2f (tcg/optimize: prefer the "op a, a, b"
form for commutative ops, 2012-09-19)?

Paolo

> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  tcg/arm/tcg-target.c |   10 ++++++++++
>  tcg/arm/tcg-target.h |    2 +-
>  2 files changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c
> index a83b295..e38fd65 100644
> --- a/tcg/arm/tcg-target.c
> +++ b/tcg/arm/tcg-target.c
> @@ -1587,6 +1587,15 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
>      case INDEX_op_movi_i32:
>          tcg_out_movi32(s, COND_AL, args[0], args[1]);
>          break;
> +    case INDEX_op_movcond_i32:
> +        /* Constraints mean that v2 is always in the same register as dest,
> +         * so we only need to do "if condition passed, move v1 to dest".
> +         */
> +        tcg_out_dat_rI(s, COND_AL, ARITH_CMP, 0,
> +                       args[1], args[2], const_args[2]);
> +        tcg_out_dat_rI(s, tcg_cond_to_arm_cond[args[5]],
> +                       ARITH_MOV, args[0], 0, args[3], const_args[3]);
> +        break;
>      case INDEX_op_add_i32:
>          c = ARITH_ADD;
>          goto gen_arith;
> @@ -1798,6 +1807,7 @@ static const TCGTargetOpDef arm_op_defs[] = {
>  
>      { INDEX_op_brcond_i32, { "r", "rI" } },
>      { INDEX_op_setcond_i32, { "r", "r", "rI" } },
> +    { INDEX_op_movcond_i32, { "r", "r", "rI", "rI", "0" } },
>  
>      /* TODO: "r", "r", "r", "r", "ri", "ri" */
>      { INDEX_op_add2_i32, { "r", "r", "r", "r", "r", "r" } },
> diff --git a/tcg/arm/tcg-target.h b/tcg/arm/tcg-target.h
> index e2299ca..0df3352 100644
> --- a/tcg/arm/tcg-target.h
> +++ b/tcg/arm/tcg-target.h
> @@ -73,7 +73,7 @@ typedef enum {
>  #define TCG_TARGET_HAS_nand_i32         0
>  #define TCG_TARGET_HAS_nor_i32          0
>  #define TCG_TARGET_HAS_deposit_i32      0
> -#define TCG_TARGET_HAS_movcond_i32      0
> +#define TCG_TARGET_HAS_movcond_i32      1
>  
>  #define TCG_TARGET_HAS_GUEST_BASE
>  
>
Richard Henderson - Sept. 27, 2012, 2:32 p.m.
On 09/26/2012 11:33 PM, Paolo Bonzini wrote:
> Should you make tcg/optimize.c prefer "movcond a, a, b" to "movcond a,
> b, a", similar to commit c2b0e2f (tcg/optimize: prefer the "op a, a, b"
> form for commutative ops, 2012-09-19)?

I explicitly went with "a, b, a" because I find it is easier to
reason with positive logic (move-if-true) than negative logic.


r~
Aurelien Jarno - Sept. 27, 2012, 7:53 p.m.
On Wed, Sep 26, 2012 at 07:48:55PM +0100, Peter Maydell wrote:
> Implement movcond_i32 for ARM, as the sequence
>   mov dst, v2   (implicitly done by the tcg common code)
>   cmp c1, c2
>   movCC dst, v1
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  tcg/arm/tcg-target.c |   10 ++++++++++
>  tcg/arm/tcg-target.h |    2 +-
>  2 files changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c
> index a83b295..e38fd65 100644
> --- a/tcg/arm/tcg-target.c
> +++ b/tcg/arm/tcg-target.c
> @@ -1587,6 +1587,15 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
>      case INDEX_op_movi_i32:
>          tcg_out_movi32(s, COND_AL, args[0], args[1]);
>          break;
> +    case INDEX_op_movcond_i32:
> +        /* Constraints mean that v2 is always in the same register as dest,
> +         * so we only need to do "if condition passed, move v1 to dest".
> +         */
> +        tcg_out_dat_rI(s, COND_AL, ARITH_CMP, 0,
> +                       args[1], args[2], const_args[2]);
> +        tcg_out_dat_rI(s, tcg_cond_to_arm_cond[args[5]],
> +                       ARITH_MOV, args[0], 0, args[3], const_args[3]);
> +        break;
>      case INDEX_op_add_i32:
>          c = ARITH_ADD;
>          goto gen_arith;
> @@ -1798,6 +1807,7 @@ static const TCGTargetOpDef arm_op_defs[] = {
>  
>      { INDEX_op_brcond_i32, { "r", "rI" } },
>      { INDEX_op_setcond_i32, { "r", "r", "rI" } },
> +    { INDEX_op_movcond_i32, { "r", "r", "rI", "rI", "0" } },
>  
>      /* TODO: "r", "r", "r", "r", "ri", "ri" */
>      { INDEX_op_add2_i32, { "r", "r", "r", "r", "r", "r" } },
> diff --git a/tcg/arm/tcg-target.h b/tcg/arm/tcg-target.h
> index e2299ca..0df3352 100644
> --- a/tcg/arm/tcg-target.h
> +++ b/tcg/arm/tcg-target.h
> @@ -73,7 +73,7 @@ typedef enum {
>  #define TCG_TARGET_HAS_nand_i32         0
>  #define TCG_TARGET_HAS_nor_i32          0
>  #define TCG_TARGET_HAS_deposit_i32      0
> -#define TCG_TARGET_HAS_movcond_i32      0
> +#define TCG_TARGET_HAS_movcond_i32      1
>  
>  #define TCG_TARGET_HAS_GUEST_BASE
>  

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>

Patch

diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c
index a83b295..e38fd65 100644
--- a/tcg/arm/tcg-target.c
+++ b/tcg/arm/tcg-target.c
@@ -1587,6 +1587,15 @@  static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
     case INDEX_op_movi_i32:
         tcg_out_movi32(s, COND_AL, args[0], args[1]);
         break;
+    case INDEX_op_movcond_i32:
+        /* Constraints mean that v2 is always in the same register as dest,
+         * so we only need to do "if condition passed, move v1 to dest".
+         */
+        tcg_out_dat_rI(s, COND_AL, ARITH_CMP, 0,
+                       args[1], args[2], const_args[2]);
+        tcg_out_dat_rI(s, tcg_cond_to_arm_cond[args[5]],
+                       ARITH_MOV, args[0], 0, args[3], const_args[3]);
+        break;
     case INDEX_op_add_i32:
         c = ARITH_ADD;
         goto gen_arith;
@@ -1798,6 +1807,7 @@  static const TCGTargetOpDef arm_op_defs[] = {
 
     { INDEX_op_brcond_i32, { "r", "rI" } },
     { INDEX_op_setcond_i32, { "r", "r", "rI" } },
+    { INDEX_op_movcond_i32, { "r", "r", "rI", "rI", "0" } },
 
     /* TODO: "r", "r", "r", "r", "ri", "ri" */
     { INDEX_op_add2_i32, { "r", "r", "r", "r", "r", "r" } },
diff --git a/tcg/arm/tcg-target.h b/tcg/arm/tcg-target.h
index e2299ca..0df3352 100644
--- a/tcg/arm/tcg-target.h
+++ b/tcg/arm/tcg-target.h
@@ -73,7 +73,7 @@  typedef enum {
 #define TCG_TARGET_HAS_nand_i32         0
 #define TCG_TARGET_HAS_nor_i32          0
 #define TCG_TARGET_HAS_deposit_i32      0
-#define TCG_TARGET_HAS_movcond_i32      0
+#define TCG_TARGET_HAS_movcond_i32      1
 
 #define TCG_TARGET_HAS_GUEST_BASE