mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2025-02-01 05:01:59 +01:00
1384b0c2ff
This patch changes the order in which we attempt to prove the independence of strided accesses. We previously did this after we knew the dependence distance was positive. With this change, we check for independence before handling the negative distance case. The patch prevents LAA from reporting forward dependences for independent strided accesses. This change was requested in the review of D19984. llvm-svn: 270072
46 lines
1.2 KiB
LLVM
46 lines
1.2 KiB
LLVM
; RUN: opt < %s -store-to-load-forwarding-conflict-detection=false -loop-accesses -analyze | FileCheck %s
|
|
|
|
; This test checks that we prove the strided accesses to be independent before
|
|
; concluding that there is a forward dependence.
|
|
|
|
; struct pair {
|
|
; int x;
|
|
; int y;
|
|
; };
|
|
;
|
|
; int independent_interleaved(struct pair *p, int z, int n) {
|
|
; int s = 0;
|
|
; for (int i = 0; i < n; i++) {
|
|
; p[i].y = z;
|
|
; s += p[i].x;
|
|
; }
|
|
; return s;
|
|
; }
|
|
|
|
; CHECK: for.body:
|
|
; CHECK-NOT: Forward:
|
|
; CHECK-NOT: store i32 %z, i32* %p_i.y, align 8 ->
|
|
; CHECK-NOT: %0 = load i32, i32* %p_i.x, align 8
|
|
|
|
%pair = type { i32, i32 }
|
|
define i32 @independent_interleaved(%pair *%p, i64 %n, i32 %z) {
|
|
entry:
|
|
br label %for.body
|
|
|
|
for.body:
|
|
%i = phi i64 [ %i.next, %for.body ], [ 0, %entry ]
|
|
%s = phi i32 [ %1, %for.body ], [ 0, %entry ]
|
|
%p_i.x = getelementptr inbounds %pair, %pair* %p, i64 %i, i32 0
|
|
%p_i.y = getelementptr inbounds %pair, %pair* %p, i64 %i, i32 1
|
|
store i32 %z, i32* %p_i.y, align 8
|
|
%0 = load i32, i32* %p_i.x, align 8
|
|
%1 = add nsw i32 %0, %s
|
|
%i.next = add nuw nsw i64 %i, 1
|
|
%cond = icmp slt i64 %i.next, %n
|
|
br i1 %cond, label %for.body, label %for.end
|
|
|
|
for.end:
|
|
%2 = phi i32 [ %1, %for.body ]
|
|
ret i32 %2
|
|
}
|