gcc/gcc41-pr23848.patch

226 lines
6.4 KiB
Diff
Raw Normal View History

2007-11-25 20:29:41 +00:00
2007-11-15 Jakub Jelinek <jakub@redhat.com>
PR middle-end/23848
* tree-ssa-ccp.c (optimize_stack_restore): New function.
(execute_fold_all_builtins): Call optimize_stack_restore for
BUILT_IN_STACK_RESTORE.
* gcc.dg/tree-ssa/pr23848-1.c: New test.
* gcc.dg/tree-ssa/pr23848-2.c: New test.
* gcc.dg/tree-ssa/pr23848-3.c: New test.
* gcc.dg/tree-ssa/pr23848-4.c: New test.
--- gcc/tree-ssa-ccp.c (revision 130205)
+++ gcc/tree-ssa-ccp.c (revision 130206)
@@ -2394,6 +2394,75 @@ fold_stmt_inplace (tree stmt)
return changed;
}
+/* Try to optimize out __builtin_stack_restore. Optimize it out
+ if there is another __builtin_stack_restore in the same basic
+ block and no calls or ASM_EXPRs are in between, or if this block's
+ only outgoing edge is to EXIT_BLOCK and there are no calls or
+ ASM_EXPRs after this __builtin_stack_restore. */
+
+static tree
+optimize_stack_restore (basic_block bb, tree call, block_stmt_iterator i)
+{
+ tree stack_save, stmt, callee;
+
+ if (TREE_CODE (call) != CALL_EXPR
+ || TREE_OPERAND (call, 1) == NULL_TREE
+ || TREE_CHAIN (TREE_OPERAND (call, 1)) != NULL_TREE
+ || TREE_CODE (TREE_VALUE (TREE_OPERAND (call, 1))) != SSA_NAME
+ || !POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (TREE_OPERAND (call, 1)))))
+ return NULL_TREE;
+
+ for (bsi_next (&i); !bsi_end_p (i); bsi_next (&i))
+ {
+ tree call;
+
+ stmt = bsi_stmt (i);
+ if (TREE_CODE (stmt) == ASM_EXPR)
+ return NULL_TREE;
+ call = get_call_expr_in (stmt);
+ if (call == NULL)
+ continue;
+
+ callee = get_callee_fndecl (call);
+ if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL)
+ return NULL_TREE;
+
+ if (DECL_FUNCTION_CODE (callee) == BUILT_IN_STACK_RESTORE)
+ break;
+ }
+
+ if (bsi_end_p (i)
+ && (! single_succ_p (bb)
+ || single_succ_edge (bb)->dest != EXIT_BLOCK_PTR))
+ return NULL_TREE;
+
+ stack_save = SSA_NAME_DEF_STMT (TREE_VALUE (TREE_OPERAND (call, 1)));
+ if (TREE_CODE (stack_save) != MODIFY_EXPR
+ || TREE_OPERAND (stack_save, 0)
+ != TREE_VALUE (TREE_OPERAND (call, 1))
+ || TREE_CODE (TREE_OPERAND (stack_save, 1)) != CALL_EXPR
+ || tree_could_throw_p (stack_save)
+ || !has_single_use (TREE_VALUE (TREE_OPERAND (call, 1))))
+ return NULL_TREE;
+
+ callee = get_callee_fndecl (TREE_OPERAND (stack_save, 1));
+ if (!callee
+ || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
+ || DECL_FUNCTION_CODE (callee) != BUILT_IN_STACK_SAVE
+ || TREE_OPERAND (TREE_OPERAND (stack_save, 1), 1) != NULL_TREE)
+ return NULL_TREE;
+
+ stmt = stack_save;
+ if (!set_rhs (&stmt,
+ build_int_cst (TREE_TYPE (TREE_VALUE (TREE_OPERAND (call,
+ 1))), 0)))
+ return NULL_TREE;
+ gcc_assert (stmt == stack_save);
+ mark_new_vars_to_rename (stmt);
+
+ return integer_zero_node;
+}
+
/* Convert EXPR into a GIMPLE value suitable for substitution on the
RHS of an assignment. Insert the necessary statements before
iterator *SI_P. */
@@ -2469,6 +2538,12 @@ execute_fold_all_builtins (void)
result = integer_zero_node;
break;
+ case BUILT_IN_STACK_RESTORE:
+ result = optimize_stack_restore (bb, *stmtp, i);
+ if (result)
+ break;
+ /* FALLTHRU */
+
default:
bsi_next (&i);
continue;
--- gcc/testsuite/gcc.dg/tree-ssa/pr23848-1.c (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/pr23848-1.c (revision 130206)
@@ -0,0 +1,32 @@
+/* PR middle-end/23848 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+void bar1 (char *, int);
+void foo1 (int size)
+{
+ char temp[size];
+ temp[size-1] = '\0';
+ bar1 (temp, size);
+}
+
+void bar2 (char *, char *, char *, char *, int);
+void foo2 (int size)
+{
+ char temp[size];
+ temp[size-1] = '\0';
+ {
+ char temp2[size];
+ {
+ char temp3[size];
+ {
+ char temp4[size];
+ bar2 (temp, temp2, temp3, temp4, size);
+ }
+ }
+ }
+}
+
+/* { dg-final { scan-tree-dump-not "__builtin_stack_save" "optimized"} } */
+/* { dg-final { scan-tree-dump-not "__builtin_stack_restore" "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/testsuite/gcc.dg/tree-ssa/pr23848-2.c (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/pr23848-2.c (revision 130206)
@@ -0,0 +1,25 @@
+/* PR middle-end/23848 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+void bar (char *, char *, char *, char *, int);
+void foo (int size)
+{
+ char temp[size];
+ temp[size-1] = '\0';
+ {
+ char temp2[size];
+ {
+ char temp3[size];
+ {
+ char temp4[size];
+ bar (temp, temp2, temp3, temp4, size);
+ }
+ }
+ bar (temp, temp2, (char *) 0, (char *) 0, size);
+ }
+}
+
+/* { dg-final { scan-tree-dump-times "__builtin_stack_save" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "__builtin_stack_restore" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/testsuite/gcc.dg/tree-ssa/pr23848-3.c (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/pr23848-3.c (revision 130206)
@@ -0,0 +1,28 @@
+/* PR middle-end/23848 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+void bar (int, char *, char *, char *, char *, int);
+void foo (int size)
+{
+ int i;
+ for (i = 0; i < size; i++)
+ {
+ char temp[size];
+ temp[size-1] = '\0';
+ {
+ char temp2[size];
+ {
+ char temp3[size];
+ {
+ char temp4[size];
+ bar (i, temp, temp2, temp3, temp4, size);
+ }
+ }
+ }
+ }
+}
+
+/* { dg-final { scan-tree-dump-times "__builtin_stack_save" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "__builtin_stack_restore" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/testsuite/gcc.dg/tree-ssa/pr23848-4.c (revision 0)
+++ gcc/testsuite/gcc.dg/tree-ssa/pr23848-4.c (revision 130206)
@@ -0,0 +1,25 @@
+/* PR middle-end/23848 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+void bar (char *, char *, char *, char *, int);
+void foo (int size)
+{
+ char temp[size];
+ temp[size-1] = '\0';
+ {
+ char temp2[size];
+ {
+ char temp3[size];
+ {
+ char temp4[size];
+ bar (temp, temp2, temp3, temp4, size);
+ }
+ }
+ __asm __volatile ("" : : "r" (&temp[0]), "r" (&temp2[0]) : "memory");
+ }
+}
+
+/* { dg-final { scan-tree-dump-times "__builtin_stack_save" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "__builtin_stack_restore" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */