[PATCH] Fix PR54098

[Richard Guenther]

This fixes PR54098 - if the original range was UNDEFINED simply
use the update and iterate once more.

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

Richard.

2012-07-26  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/54098
	* tree-vrp.c (vrp_visit_phi_node): Iterate once more if the
	original range was UNDEFINED.

	* gcc.dg/torture/pr54098.c: New testcase.

Index: gcc/tree-vrp.c
===================================================================
*** gcc/tree-vrp.c	(revision 189882)
--- gcc/tree-vrp.c	(working copy)
*************** vrp_visit_phi_node (gimple phi)
*** 7684,7693 ****
       when the new value is slightly bigger or smaller than the
       previous one.  We don't do this if we have seen a new executable
       edge; this helps us avoid an overflow infinity for conditionals
!      which are not in a loop.  */
    if (edges > 0
        && gimple_phi_num_args (phi) > 1
!       && edges == old_edges)
      {
        int cmp_min = compare_values (lhs_vr->min, vr_result.min);
        int cmp_max = compare_values (lhs_vr->max, vr_result.max);
--- 7684,7695 ----
       when the new value is slightly bigger or smaller than the
       previous one.  We don't do this if we have seen a new executable
       edge; this helps us avoid an overflow infinity for conditionals
!      which are not in a loop.  If the old value-range was VR_UNDEFINED
!      use the updated range and iterate one more time.  */
    if (edges > 0
        && gimple_phi_num_args (phi) > 1
!       && edges == old_edges
!       && lhs_vr->type != VR_UNDEFINED)
      {
        int cmp_min = compare_values (lhs_vr->min, vr_result.min);
        int cmp_max = compare_values (lhs_vr->max, vr_result.max);
Index: gcc/testsuite/gcc.dg/torture/pr54098.c
===================================================================
*** gcc/testsuite/gcc.dg/torture/pr54098.c	(revision 0)
--- gcc/testsuite/gcc.dg/torture/pr54098.c	(working copy)
***************
*** 0 ****
--- 1,72 ----
+ /* { dg-do compile } */
+ 
+ extern int printf(const char *, ...);
+ struct list_head {
+ 	struct list_head *next, *prev;
+ };
+ struct resource {
+ 	unsigned long long start;
+ 	unsigned long long end;
+ 	unsigned long flags;
+ 	struct resource *parent, *sibling, *child;
+ };
+ struct pci_dev {
+ 	struct list_head bus_list;
+ 	struct resource resource[12];
+ };
+ struct pci_bus {
+ 	struct list_head devices;
+ 	unsigned char secondary;
+ 	unsigned char subordinate;
+ };
+ struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n);
+ static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned long type) {
+ 	int i;
+ 	struct resource *r;
+ 	unsigned long type_mask = 0x00000100 | 0x00000200 | 0x00002000;
+ 	for (i = 0; (r = pci_bus_resource_n(bus, i)) || i < 4; i++) {
+ 		if (r && (r->flags & type_mask) == type && !r->parent) return r;
+ 	}
+ 	return ((void *)0);
+ }
+ static unsigned long long calculate_memsize(unsigned long long size, unsigned long long min_size, unsigned long long size1, unsigned long long old_size, unsigned long long align) {
+ 	if (old_size == 1 ) old_size = 0;
+ 	if (size < old_size) size = old_size;
+ 	return size;
+ }
+ void pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type, unsigned long long min_size, unsigned long long add_size, void *realloc_head) {
+ 	struct pci_dev *dev;
+ 	unsigned long long min_align, align, size, size0, size1;
+ 	int order;
+ 	struct resource *b_res = find_free_bus_resource(bus, type);
+ 	unsigned long long children_add_size = 0;
+ 	if (!b_res) return;
+ 	for (dev = ({
+ 				const typeof( ((typeof(*dev) *)0)->bus_list ) *__mptr = ((&bus->devices)->next);
+ 				(typeof(*dev) *)( (char *)__mptr - __builtin_offsetof(typeof(*dev),bus_list) );
+ 				}
+ 		   );
+ 			&dev->bus_list != (&bus->devices);
+ 			dev = ({
+ 				const typeof( ((typeof(*dev) *)0)->bus_list ) *__mptr = (dev->bus_list.next);
+ 				(typeof(*dev) *)( (char *)__mptr - __builtin_offsetof(typeof(*dev),bus_list) );
+ 				}
+ 			      )) {
+ 		int i;
+ 		for (i = 0; i < 12; i++) {
+ 			struct resource *r = &dev->resource[i];
+ 			unsigned long long r_size;
+ 			if (r->parent || (r->flags & mask) != type) continue;
+ 			r_size = r->end - r->start + 1;
+ 			if (order > 11) {
+ 				printf("%d: %pR %#llx\n", i, r, (unsigned long long) align);
+ 			}
+ 			size += r_size;
+ 		}
+ 	}
+ 	if (children_add_size > add_size) add_size = children_add_size;
+ 	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 : calculate_memsize(size, min_size+add_size, 0, b_res->end - b_res->start + 1, min_align);
+ 	if (!size0 && !size1) {
+ 		printf("%pR %02x-%02x\n", b_res, bus->secondary, bus->subordinate);
+ 	}
+ }