When gvn decides to replace an instruction with another, we have to patch the

replacement to make it at least as generic as the instruction being replaced.
This includes:
* dropping nsw/nuw flags
* getting the least restrictive tbaa and fpmath metadata
* merging ranges

Fixes PR12979.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157958 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 101 insertions, 0 deletions

diff --git a/test/Transforms/GVN/range.ll b/test/Transforms/GVN/range.ll
new file mode 100644
index 0000000..3759c41
--- /dev/null
+++ b/test/Transforms/GVN/range.ll
@@ -0,0 +1,101 @@
+; RUN: opt %s -basicaa -gvn -S -o - | FileCheck %s
+
+define i32 @test1(i32* %p) {
+; CHECK: @test1(i32* %p)
+; CHECK: %a = load i32* %p, !range !0
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !0
+  %b = load i32* %p, !range !0
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test2(i32* %p) {
+; CHECK: @test2(i32* %p)
+; CHECK: %a = load i32* %p
+; CHECK-NOT: range
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !0
+  %b = load i32* %p
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test3(i32* %p) {
+; CHECK: @test3(i32* %p)
+; CHECK: %a = load i32* %p, !range ![[DISJOINT_RANGE:[0-9]+]]
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !0
+  %b = load i32* %p, !range !1
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test4(i32* %p) {
+; CHECK: @test4(i32* %p)
+; CHECK: %a = load i32* %p, !range ![[MERGED_RANGE:[0-9]+]]
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !0
+  %b = load i32* %p, !range !2
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test5(i32* %p) {
+; CHECK: @test5(i32* %p)
+; CHECK: %a = load i32* %p, !range ![[MERGED_SIGNED_RANGE:[0-9]+]]
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !3
+  %b = load i32* %p, !range !4
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test6(i32* %p) {
+; CHECK: @test6(i32* %p)
+; CHECK: %a = load i32* %p, !range ![[MERGED_TEST6:[0-9]+]]
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !5
+  %b = load i32* %p, !range !6
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test7(i32* %p) {
+; CHECK: @test7(i32* %p)
+; CHECK: %a = load i32* %p, !range ![[MERGED_TEST7:[0-9]+]]
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !7
+  %b = load i32* %p, !range !8
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+define i32 @test8(i32* %p) {
+; CHECK: @test8(i32* %p)
+; CHECK: %a = load i32* %p
+; CHECK-NOT: range
+; CHECK: %c = add i32 %a, %a
+  %a = load i32* %p, !range !9
+  %b = load i32* %p, !range !10
+  %c = add i32 %a, %b
+  ret i32 %c
+}
+
+; CHECK: ![[DISJOINT_RANGE]] = metadata !{i32 0, i32 2, i32 3, i32 5}
+; CHECK: ![[MERGED_RANGE]] = metadata !{i32 0, i32 5}
+; CHECK: ![[MERGED_SIGNED_RANGE]] = metadata !{i32 -3, i32 -2, i32 1, i32 2}
+; CHECK: ![[MERGED_TEST6]] = metadata !{i32 10, i32 1}
+; CHECK: ![[MERGED_TEST7]] = metadata !{i32 3, i32 4, i32 5, i32 2}
+
+!0 = metadata !{i32 0, i32 2}
+!1 = metadata !{i32 3, i32 5}
+!2 = metadata !{i32 2, i32 5}
+!3 = metadata !{i32 -3, i32 -2}
+!4 = metadata !{i32 1, i32 2}
+!5 = metadata !{i32 10, i32 1}
+!6 = metadata !{i32 12, i32 13}
+!7 = metadata !{i32 1, i32 2, i32 3, i32 4}
+!8 = metadata !{i32 5, i32 1}
+!9 = metadata !{i32 1, i32 5}
+!10 = metadata !{i32 5, i32 1}