[PATCH] Fix PR31976, PR34093, operand memory overflow

[Richard Guenther <rguenther at suse dot de>]

This patch removes the assert for the number of ssa operands never
exceeding a specific constant number, but instead allocates a separate
buffer for large number of operands.  As we can systematically trigger
this case this is the correct approach for 4.3 and I believe in general.

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to mainline.

Richard.

2008-01-02  Richard Guenther  <rguenther@suse.de>

	PR middle-end/34093
	PR middle-end/31976
	* tree-ssa-operands.c (ssa_operand_alloc): Also allocate a buffer
	for very large number of operands instead of ICEing.

	* gcc.c-torture/compile/pr34093.c: New testcase.

Index: tree-ssa-operands.c
===================================================================
*** tree-ssa-operands.c	(revision 131254)
--- tree-ssa-operands.c	(working copy)
*************** ssa_operand_alloc (unsigned size)
*** 477,487 ****
          gimple_ssa_operands (cfun)->ssa_operand_mem_size
  	  = OP_SIZE_3 * sizeof (struct voptype_d);
  
!       /* Fail if there is not enough space.  If there are this many operands
! 	 required, first make sure there isn't a different problem causing this
! 	 many operands.  If the decision is that this is OK, then we can 
! 	 specially allocate a buffer just for this request.  */
!       gcc_assert (size <= gimple_ssa_operands (cfun)->ssa_operand_mem_size);
  
        ptr = (struct ssa_operand_memory_d *) 
  	      ggc_alloc (sizeof (struct ssa_operand_memory_d) 
--- 477,486 ----
          gimple_ssa_operands (cfun)->ssa_operand_mem_size
  	  = OP_SIZE_3 * sizeof (struct voptype_d);
  
!       /* We can reliably trigger the case that we need arbitrary many
! 	 operands (see PR34093), so allocate a buffer just for this request.  */
!       if (size > gimple_ssa_operands (cfun)->ssa_operand_mem_size)
! 	gimple_ssa_operands (cfun)->ssa_operand_mem_size = size;
  
        ptr = (struct ssa_operand_memory_d *) 
  	      ggc_alloc (sizeof (struct ssa_operand_memory_d) 
Index: testsuite/gcc.c-torture/compile/pr34093.c
===================================================================
*** testsuite/gcc.c-torture/compile/pr34093.c	(revision 0)
--- testsuite/gcc.c-torture/compile/pr34093.c	(revision 0)
***************
*** 0 ****
--- 1,39 ----
+ struct X { int i; int j; };
+ #define FOO struct X
+ #define FOO10(x) FOO x ## 0; FOO x ## 1; FOO x ## 2; FOO x ## 3; FOO x ## 4; FOO x ## 5; FOO x ## 6; FOO x ## 7; FOO x ## 8; FOO x ## 9;
+ #define FOO100(x) FOO10(x ## 0) FOO10(x ## 1) FOO10(x ## 2) FOO10(x ## 3) FOO10(x ## 4) FOO10(x ## 5) FOO10(x ## 6) FOO10(x ## 7) FOO10(x ## 8) FOO10(x ## 9)
+   FOO100(x0)
+   FOO100(x1)
+   FOO100(x2)
+   FOO100(x3)
+   FOO100(x4)
+   FOO100(x5)
+   FOO100(x6)
+   FOO100(x7)
+   FOO100(x8)
+   FOO100(x9)
+ 
+ #define COO(n,f) case n: p = &f; break;
+ #define COO10(n,f) COO(n ## 0, f ## 0) COO(n ## 1, f ## 1) COO(n ## 2, f ## 2) COO(n ## 3, f ## 3) COO(n ## 4, f ## 4) COO(n ## 5, f ## 5) COO(n ## 6, f ## 6) COO(n ## 7, f ## 7) COO(n ## 8, f ## 8) COO(n ## 9, f ## 9)
+ #define COO100(n,f) COO10(n ## 0, f ## 0) COO10(n ## 1, f ## 1) COO10(n ## 2, f ## 2) COO10(n ## 3, f ## 3) COO10(n ## 4, f ## 4) COO10(n ## 5, f ## 5) COO10(n ## 6, f ## 6) COO10(n ## 7, f ## 7) COO10(n ## 8, f ## 8) COO10(n ## 9, f ## 9)
+ 
+ int foo(int i)
+ {
+   struct X *p = 0;
+   x000.i = 0;
+   x599.j = 0;
+   switch (i)
+     {
+   COO100(1, x0)
+   COO100(2, x1)
+   COO100(3, x2)
+   COO100(4, x3)
+   COO100(5, x4)
+   COO100(6, x5)
+   COO100(7, x6)
+   COO100(8, x7)
+   COO100(9, x8)
+   COO100(10, x9)
+     }
+   return p->j;
+ }