Re: [PATCH] Explicit register earlyclobber fix

[Jeff Law]

On 09/22/2015 12:50 PM, Richard Henderson wrote:

+asm_constraint_earlyclobber (const char *constraint)
+{
+  while (*constraint != 0)
+    {
+      if (*constraint == '&')
+       return true;
+      ++constraint;
+    }
+  return false;
+}

This would be

   return strchr (constraint, '&') != NULL;

but we don't actually have to search the whole string, surely.  I'd be
surprised if early clobber could be anywhere except at the start of the 
constraint.
And doesn't it have to be =& and always at the start for an asm 
constraint?  For operands in patterns, we have to consider operand 
alternatives, but that's not on issue here.