[Bug middle-end/36253] Caller-save stack slot may not have proper alignment

[hjl dot tools at gmail dot com]

------- Comment #1 from hjl dot tools at gmail dot com  2008-05-17 02:17 -------
With this patch to verify alignment of caller-save slot:

Index: caller-save.c
===================================================================
--- caller-save.c       (revision 2603)
+++ caller-save.c       (working copy)
@@ -704,6 +704,12 @@ insert_restore (struct insn_chain *chain
     mem = adjust_address (mem, save_mode[regno], 0);
   else
     mem = copy_rtx (mem);
+
+  /* Verify that the alignment of spill space is equal to or greater
+     than required.  */
+  if (GET_MODE_ALIGNMENT (GET_MODE (mem)) > MEM_ALIGN (mem))
+    gcc_unreachable ();
+
   pat = gen_rtx_SET (VOIDmode,
                     gen_rtx_REG (GET_MODE (mem),
                                  regno), mem);
@@ -776,6 +782,12 @@ insert_save (struct insn_chain *chain, i
     mem = adjust_address (mem, save_mode[regno], 0);
   else
     mem = copy_rtx (mem);
+
+  /* Verify that the alignment of spill space is equal to or greater
+     than required.  */
+  if (GET_MODE_ALIGNMENT (GET_MODE (mem)) > MEM_ALIGN (mem))
+    gcc_unreachable ();
+
   pat = gen_rtx_SET (VOIDmode, mem,
                     gen_rtx_REG (GET_MODE (mem),
                                  regno));
Index: function.c
===================================================================
--- function.c  (revision 2603)
+++ function.c  (working copy)
@@ -341,7 +341,7 @@ assign_stack_local (enum machine_mode mo
 {
   rtx x, addr;
   int bigend_correction = 0;
-  unsigned int alignment;
+  unsigned int alignment, alignment_in_bits;
   int frame_off, frame_alignment, frame_phase;

   if (align == 0)
@@ -378,8 +378,10 @@ assign_stack_local (enum machine_mode mo
   if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
     alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;

-  if (crtl->stack_alignment_needed < alignment * BITS_PER_UNIT)
-    crtl->stack_alignment_needed = alignment * BITS_PER_UNIT;
+  alignment_in_bits = alignment * BITS_PER_UNIT;
+
+  if (crtl->stack_alignment_needed < alignment_in_bits)
+    crtl->stack_alignment_needed = alignment_in_bits;

   /* Calculate how many bytes the start of local variables is off from
      stack alignment.  */
@@ -432,6 +434,7 @@ assign_stack_local (enum machine_mode mo
     frame_offset += size;

   x = gen_rtx_MEM (mode, addr);
+  set_mem_align (x, alignment_in_bits);
   MEM_NOTRAP_P (x) = 1;

   stack_slot_list

On Linux/Intel64, I got

gnu/java/awt/GradientPaintContext.java: In class
'gnu.java.awt.GradientPaintContext':
gnu/java/awt/GradientPaintContext.java: In method
'gnu.java.awt.GradientPaintContext.getRaster(int,int,int,int)':
In file included from gnu/java/awt/EventModifier.java:105,
                 from gnu/java/awt/EmbeddedWindow.java:137,
                 from gnu/java/awt/ComponentReshapeEvent.java:84,
                 from gnu/java/awt/ComponentDataBlitOp.java:154,
                 from gnu/java/awt/ClasspathToolkit.java:231,
                 from gnu/java/awt/ClasspathGraphicsEnvironment.java:65,
                 from gnu/java/awt/Buffers.java:222,
                 from
/export/gnu/src/gcc-expand/gcc/libjava/classpath/gnu/java/awt/BitwiseXORComposite.java:292,
                 from
/export/gnu/src/gcc-expand/gcc/libjava/classpath/gnu/java/awt/BitwiseXORComposite.java:202,
                 from gnu/java/awt/BitwiseXORComposite.java:130,
                 from gnu/java/awt/BitMaskExtent.java:77,
                 from
/export/gnu/src/gcc-expand/gcc/libjava/classpath/gnu/java/awt/AWTUtilities.java:253,
                 from
/export/gnu/src/gcc-expand/gcc/libjava/classpath/gnu/java/awt/AWTUtilities.java:296,
                 from gnu/java/awt/AWTUtilities.java:895,
                 from <built-in>:63:
gnu/java/awt/GradientPaintContext.java:153: internal compiler error: in
insert_save, at caller-save.c:789
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
make[6]: *** [gnu/java/awt.lo] Error 1
make[6]: *** Waiting for unfinished jobs....

when I was building 32bit libjava.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36253