[CGP] Fix the rematerialization of gc.relocates
If we want to substitute the relocation of derived pointer with gep of base then
we must ensure that relocation of base dominates the relocation of derived pointer.
Currently only check for basic block is present. However it is possible that both
relocation are in the same basic block but relocation of derived pointer is defined
earlier.
The patch moves the relocation of base pointer right before relocation of derived
pointer in this case.
Reviewers: sanjoy,artagnon,igor-laevsky,reames
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36462
llvm-svn: 311067
diff --git a/llvm/test/Transforms/CodeGenPrepare/statepoint-relocate.ll b/llvm/test/Transforms/CodeGenPrepare/statepoint-relocate.ll
index b31dfe7..af911c3 100644
--- a/llvm/test/Transforms/CodeGenPrepare/statepoint-relocate.ll
+++ b/llvm/test/Transforms/CodeGenPrepare/statepoint-relocate.ll
@@ -122,6 +122,28 @@
ret i32 %ret-base
}
+define i32 @test_sor_noop_same_bb(i1 %external-cond, i32* %base) gc "statepoint-example" {
+; CHECK-LABEL: @test_sor_noop_same_bb
+; Here base relocate doesn't dominate derived relocate. Make sure that we don't
+; produce undefined use of the relocated base pointer.
+entry:
+ %ptr1 = getelementptr i32, i32* %base, i32 15
+ ; CHECK: getelementptr i32, i32* %base, i32 15
+ %ptr2 = getelementptr i32, i32* %base, i32 5
+ ; CHECK: getelementptr i32, i32* %base, i32 5
+ %tok = call token (i64, i32, i1 ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_i1f(i64 0, i32 0, i1 ()* @return_i1, i32 0, i32 0, i32 0, i32 0, i32* %base, i32* %ptr1, i32* %ptr2)
+ ; CHECK: call i32* @llvm.experimental.gc.relocate.p0i32(token %tok, i32 7, i32 7)
+ %ptr2-new = call i32* @llvm.experimental.gc.relocate.p0i32(token %tok, i32 7, i32 9)
+ %ret2-new = load i32, i32* %ptr2-new
+ ; CHECK: getelementptr i32, i32* %base-new, i32 5
+ %ptr1-new = call i32* @llvm.experimental.gc.relocate.p0i32(token %tok, i32 7, i32 8)
+ %ret1-new = load i32, i32* %ptr1-new
+ ; CHECK: getelementptr i32, i32* %base-new, i32 15
+ %base-new = call i32* @llvm.experimental.gc.relocate.p0i32(token %tok, i32 7, i32 7)
+ %ret-new = add i32 %ret2-new, %ret1-new
+ ret i32 %ret-new
+}
+
declare token @llvm.experimental.gc.statepoint.p0f_i1f(i64, i32, i1 ()*, i32, i32, ...)
declare i32* @llvm.experimental.gc.relocate.p0i32(token, i32, i32)
declare [3 x i32]* @llvm.experimental.gc.relocate.p0a3i32(token, i32, i32)