[Bug target/37010] -Os passes __m128 on stack with wrong alignment

[hjl dot tools at gmail dot com]

------- Comment #3 from hjl dot tools at gmail dot com  2008-08-03 18:40 -------
Joey, when we compute frame layout, we don't count the duplicated
return address pushed onto stack when DRAP is used. Also when we
push return address, shouldn't we use -UNITS_PER_WORD, instead of
-(STACK_BOUNDARY / BITS_PER_UNIT))? On MacOS, STACK_BOUNDARY is
128 on ia32. Does this patch make sense?

--- ./i386.c.drap       2008-08-03 09:50:05.000000000 -0700
+++ ./i386.c    2008-08-03 11:36:40.000000000 -0700
@@ -7291,6 +7291,10 @@ ix86_compute_frame_layout (struct ix86_f
   if (stack_realign_fp)
     offset = (offset + stack_alignment_needed -1) & -stack_alignment_needed;

+  /* Duplicated return address when DRAP is used.  */
+  if (crtl->drap_reg && crtl->stack_realign_needed)
+    offset += UNITS_PER_WORD;
+
   /* Register save area */
   offset += frame->nregs * UNITS_PER_WORD;

@@ -7692,8 +7696,7 @@ ix86_expand_prologue (void)
         expand_builtin_return_addr etc.  */
       x = crtl->drap_reg;
       x = gen_frame_mem (Pmode,
-                         plus_constant (x,
-                                       -(STACK_BOUNDARY / BITS_PER_UNIT)));
+                         plus_constant (x, -UNITS_PER_WORD));
       insn = emit_insn (gen_push (x));
       RTX_FRAME_RELATED_P (insn) = 1;
     }


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
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                 CC|                            |hubicka at ucw dot cz


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37010