diff mbox

-fuse-caller-save - Collect register usage information

Message ID 53A2DA1D.80909@mentor.com
State New
Headers show

Commit Message

Tom de Vries June 19, 2014, 12:39 p.m. UTC 
On 19-06-14 07:13, Richard Henderson wrote:
> On 05/19/2014 07:30 AM, Tom de Vries wrote:
>> >+  for (insn = get_insns (); insn != NULL_RTX; insn = next_insn (insn))
>> >+    {
>> >+      HARD_REG_SET insn_used_regs;
>> >+
>> >+      if (!NONDEBUG_INSN_P (insn))
>> >+	continue;
>> >+
>> >+      find_all_hard_reg_sets (insn, &insn_used_regs, false);
>> >+
>> >+      if (CALL_P (insn)
>> >+	  && !get_call_reg_set_usage (insn, &insn_used_regs, call_used_reg_set))
>> >+	{
>> >+	  CLEAR_HARD_REG_SET (node->function_used_regs);
>> >+	  return;
>> >+	}
>> >+
>> >+      IOR_HARD_REG_SET (node->function_used_regs, insn_used_regs);
>> >+    }
> As an aside, wouldn't it work out better if we collect into a local variable
> instead of writing to memory here in node->function_used_regs each time?

Richard,

Agreed. This patch implements that. I'll bootstrap and reg-test on x86_64 and 
commit as obvious.

Thanks,
- Tom

Comments

Richard Henderson June 19, 2014, 3:35 p.m. UTC | #1 
On 06/19/2014 05:39 AM, Tom de Vries wrote:
> 
> 2014-06-19  Tom de Vries  <tom@codesourcery.com>
> 
> 	* final.c (collect_fn_hard_reg_usage): Add and use variable
> 	function_used_regs.

Looks good, thanks.


r~
diff mbox

Patch

2014-06-19  Tom de Vries  <tom@codesourcery.com>

	* final.c (collect_fn_hard_reg_usage): Add and use variable
	function_used_regs.

diff --git a/gcc/final.c b/gcc/final.c
index 4f08073..e39930d 100644
--- a/gcc/final.c
+++ b/gcc/final.c
@@ -4760,13 +4760,13 @@  collect_fn_hard_reg_usage (void)
   int i;
 #endif
   struct cgraph_rtl_info *node;
+  HARD_REG_SET function_used_regs;
 
   /* ??? To be removed when all the ports have been fixed.  */
   if (!targetm.call_fusage_contains_non_callee_clobbers)
     return;
 
-  node = cgraph_rtl_info (current_function_decl);
-  gcc_assert (node != NULL);
+  CLEAR_HARD_REG_SET (function_used_regs);
 
   for (insn = get_insns (); insn != NULL_RTX; insn = next_insn (insn))
     {
@@ -4779,25 +4779,26 @@  collect_fn_hard_reg_usage (void)
 
       if (CALL_P (insn)
 	  && !get_call_reg_set_usage (insn, &insn_used_regs, call_used_reg_set))
-	{
-	  CLEAR_HARD_REG_SET (node->function_used_regs);
-	  return;
-	}
+	return;
 
-      IOR_HARD_REG_SET (node->function_used_regs, insn_used_regs);
+      IOR_HARD_REG_SET (function_used_regs, insn_used_regs);
     }
 
   /* Be conservative - mark fixed and global registers as used.  */
-  IOR_HARD_REG_SET (node->function_used_regs, fixed_reg_set);
+  IOR_HARD_REG_SET (function_used_regs, fixed_reg_set);
 
 #ifdef STACK_REGS
   /* Handle STACK_REGS conservatively, since the df-framework does not
      provide accurate information for them.  */
 
   for (i = FIRST_STACK_REG; i <= LAST_STACK_REG; i++)
-    SET_HARD_REG_BIT (node->function_used_regs, i);
+    SET_HARD_REG_BIT (function_used_regs, i);
 #endif
 
+  node = cgraph_rtl_info (current_function_decl);
+  gcc_assert (node != NULL);
+
+  COPY_HARD_REG_SET (node->function_used_regs, function_used_regs);
   node->function_used_regs_valid = 1;
 }
 
-- 
1.9.1