> It's definitely not ok at this stage but at most for next stage1. OK. I may wait until next stage1.
> This is a very narrow pattern-match. It doesn't allow for &a[i].x for
> example,
> even if a[i] is a one-element structure. I think the canonical way of
> handling
> ADDR_EXPR is to use sth like
>
> base = get_inner_reference (TREE_OPERAND (rhs1, 0), ..., &offset, ...);
> base = build1 (ADDR_EXPR, TREE_TYPE (rhs1), base);
> chrec1 = analyze_scalar_evolution (loop, base);
> chrec2 = analyze_scalar_evolution (loop, offset);
> chrec1 = chrec_convert (type, chrec1, at_stmt);
> chrec2 = chrec_convert (TREE_TYPE (offset), chrec2, at_stmt);
> res = chrec_fold_plus (type, chrec1, chrec2);
>
> where you probably need to handle scev_not_known when analyzing offset
> (which might be NULL). You also need to add bitpos to the base address
> (in bytes, of course). Note that the &MEM_REF case would naturally
> work
> with this as well.
OK. New patch is like below, and bootstrapped on x86-32.
ChangeLog:
2012-01-20 Jiangning Liu <jiangning....@arm.com>
* tree-scalar-evolution (interpret_rhs_expr): generate chrec for
array reference and component reference.
ChangeLog for testsuite:
2012-01-20 Jiangning Liu <jiangning....@arm.com>
* gcc.dg/tree-ssa/scev-3.c: New.
* gcc.dg/tree-ssa/scev-4.c: New.
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/scev-3.c
b/gcc/testsuite/gcc.dg/tree-ssa/scev-3.c
new file mode 100644
index 0000000..28d5c93
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/scev-3.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+int *a_p;
+int a[1000];
+
+f(int k)
+{
+ int i;
+
+ for (i=k; i<1000; i+=k) {
+ a_p = &a[i];
+ *a_p = 100;
+ }
+}
+
+/* { dg-final { scan-tree-dump-times "&a" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/scev-4.c
b/gcc/testsuite/gcc.dg/tree-ssa/scev-4.c
new file mode 100644
index 0000000..6c1e530
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/scev-4.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+typedef struct {
+ int x;
+ int y;
+} S;
+
+int *a_p;
+S a[1000];
+
+f(int k)
+{
+ int i;
+
+ for (i=k; i<1000; i+=k) {
+ a_p = &a[i].y;
+ *a_p = 100;
+ }
+}
+
+/* { dg-final { scan-tree-dump-times "&a" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/tree-scalar-evolution.c b/gcc/tree-scalar-evolution.c
index 2077c8d..4e06b75
--- a/gcc/tree-scalar-evolution.c
+++ b/gcc/tree-scalar-evolution.c
@@ -1712,16 +1712,61 @@ interpret_rhs_expr (struct loop *loop, gimple
at_stmt,
switch (code)
{
case ADDR_EXPR:
- /* Handle &MEM[ptr + CST] which is equivalent to POINTER_PLUS_EXPR.
*/
- if (TREE_CODE (TREE_OPERAND (rhs1, 0)) != MEM_REF)
- {
- res = chrec_dont_know;
- break;
- }
+ if (TREE_CODE (TREE_OPERAND (rhs1, 0)) == ARRAY_REF
+ || TREE_CODE (TREE_OPERAND (rhs1, 0)) == MEM_REF
+ || TREE_CODE (TREE_OPERAND (rhs1, 0)) == COMPONENT_REF)
+ {
+ enum machine_mode mode;
+ HOST_WIDE_INT bitsize, bitpos;
+ int unsignedp;
+ int volatilep = 0;
+ tree base, offset;
+ tree chrec3;
+
+ base = get_inner_reference (TREE_OPERAND (rhs1, 0),
+ &bitsize, &bitpos, &offset,
+ &mode, &unsignedp, &volatilep, false);
+
+ if (TREE_CODE (base) == MEM_REF)
+ {
+ rhs2 = TREE_OPERAND (base, 1);
+ rhs1 = TREE_OPERAND (base, 0);
+
+ chrec1 = analyze_scalar_evolution (loop, rhs1);
+ chrec2 = analyze_scalar_evolution (loop, rhs2);
+ chrec1 = chrec_convert (type, chrec1, at_stmt);
+ chrec2 = chrec_convert (TREE_TYPE (rhs2), chrec2, at_stmt);
+ res = chrec_fold_plus (type, chrec1, chrec2);
+ }
+ else
+ {
+ base = build1 (ADDR_EXPR, TREE_TYPE (rhs1), base);
+ chrec1 = analyze_scalar_evolution (loop, base);
+ chrec1 = chrec_convert (type, chrec1, at_stmt);
+ res = chrec1;
+ }
- rhs2 = TREE_OPERAND (TREE_OPERAND (rhs1, 0), 1);
- rhs1 = TREE_OPERAND (TREE_OPERAND (rhs1, 0), 0);
- /* Fall through. */
+ if (offset != NULL_TREE)
+ {
+ chrec2 = analyze_scalar_evolution (loop, offset);
+ chrec2 = chrec_convert (TREE_TYPE (offset), chrec2, at_stmt);
+ res = chrec_fold_plus (type, res, chrec2);
+ }
+
+ if (bitpos)
+ {
+ gcc_assert ((bitpos % BITS_PER_UNIT) == 0);
+
+ chrec3 = build_int_cst (integer_type_node,
+ bitpos / BITS_PER_UNIT);
+ chrec3 = analyze_scalar_evolution (loop, chrec3);
+ chrec3 = chrec_convert (integer_type_node, chrec3, at_stmt);
+ res = chrec_fold_plus (type, res, chrec3);
+ }
+ }
+ else
+ res = chrec_dont_know;
+ break;
case POINTER_PLUS_EXPR:
chrec1 = analyze_scalar_evolution (loop, rhs1);
Thanks,
-Jiangning
scev-2.patch
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