Re: PATCH [3/n] X32: Promote pointers to Pmode

[H.J. Lu]

On Wed, Jul 13, 2011 at 8:37 AM, Richard Henderson <r...@redhat.com> wrote:
> On 07/13/2011 08:35 AM, H.J. Lu wrote:
>> On Wed, Jul 13, 2011 at 8:27 AM, Richard Henderson <r...@redhat.com> wrote:
>>> On 07/13/2011 07:02 AM, H.J. Lu wrote:
>>>> Hi Richard,
>>>>
>>>> Is my patch OK?
>>>
>>> No, I don't think it is.
>>>
>>
>> What is your suggestion?
>
> Promote the return value.  If that means it doesn't match function_value,
> then I suggest that function_value is wrong.
>
>
> r~
>

This is the patch I am testing.  I will check it in if it works.

Thanks.

-- 
H.J.
---
2011-07-21  H.J. Lu  <hongjiu...@intel.com>

        * config/i386/i386.c (function_value_64): Always return pointers
        in Pmode.
        (ix86_promote_function_mode): New.
        (TARGET_PROMOTE_FUNCTION_MODE): Likewise.

2011-07-21  H.J. Lu  <hongjiu...@intel.com>

	* config/i386/i386.c (function_value_64): Always return pointers
	in Pmode.
	(ix86_promote_function_mode): New.
	(TARGET_PROMOTE_FUNCTION_MODE): Likewise.

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index da6c888..32af303 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -7078,6 +7078,11 @@ function_value_64 (enum machine_mode orig_mode, enum machine_mode mode,
 	  return gen_rtx_REG (mode, AX_REG);
 	}
     }
+  else if (POINTER_TYPE_P (valtype))
+    {
+      /* Pointers are always returned in Pmode. */
+      mode = Pmode;
+    }
 
   ret = construct_container (mode, orig_mode, valtype, 1,
 			     X86_64_REGPARM_MAX, X86_64_SSE_REGPARM_MAX,
@@ -7147,6 +7152,22 @@ ix86_function_value (const_tree valtype, const_tree fntype_or_decl,
   return ix86_function_value_1 (valtype, fntype_or_decl, orig_mode, mode);
 }
 
+/* Pointer function arguments and return values are promoted to Pmode.  */
+
+static enum machine_mode
+ix86_promote_function_mode (const_tree type, enum machine_mode mode,
+			    int *punsignedp, const_tree fntype,
+			    int for_return)
+{
+  if (type != NULL_TREE && POINTER_TYPE_P (type))
+    {
+      *punsignedp = POINTERS_EXTEND_UNSIGNED;
+      return Pmode;
+    }
+  return default_promote_function_mode (type, mode, punsignedp, fntype,
+					for_return);
+}
+
 rtx
 ix86_libcall_value (enum machine_mode mode)
 {
@@ -34970,6 +35055,9 @@ ix86_autovectorize_vector_sizes (void)
 #undef TARGET_FUNCTION_VALUE_REGNO_P
 #define TARGET_FUNCTION_VALUE_REGNO_P ix86_function_value_regno_p
 
+#undef TARGET_PROMOTE_FUNCTION_MODE
+#define TARGET_PROMOTE_FUNCTION_MODE ix86_promote_function_mode
+
 #undef TARGET_SECONDARY_RELOAD
 #define TARGET_SECONDARY_RELOAD ix86_secondary_reload