From: Davide Italiano <davide@freebsd.org>
Date: Fri, 19 May 2017 19:41:11 +0000 (+0000)
Subject: [InstCombine] *Actually* commit the test showing the miscompile.
X-Git-Tag: android-x86-7.1-r4~16033
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=ef0829e2df9959c28a3a47bd310fcacb580b7723;p=android-x86%2Fexternal-llvm.git

[InstCombine] *Actually* commit the test showing the miscompile.

Clarify a comment while I'm here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303447 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/test/Transforms/InstCombine/cast.ll b/test/Transforms/InstCombine/cast.ll
index 74ea67ac72b..2f15617e065 100644
--- a/test/Transforms/InstCombine/cast.ll
+++ b/test/Transforms/InstCombine/cast.ll
@@ -1471,7 +1471,7 @@ define i32 @test93(i32 %A) {
   ret i32 %D
 }
 
-; The following three tests show a miscompile of sext + lshr + trunc patterns.
+; The following four tests sext + lshr + trunc patterns.
 ; PR33078
 
 define i8 @pr33078_1(i8 %A) {
@@ -1509,3 +1509,15 @@ define i4 @pr33078_3(i8 %A) {
   %D = trunc i16 %C to i4
   ret i4 %D
 }
+
+define i8 @pr33078_4(i3 %x) {
+; Don't turn this in an `ashr`. This was getting miscompiled
+; CHECK-LABEL: @pr33078_4(
+; CHECK-NEXT:    [[C:%.*]] = ashr i3 %x, 2
+; CHECK-NEXT:    [[B:%.*]] = sext i3 [[C]] to i8
+; CHECK-NEXT:    ret i8 [[D]]
+  %B = sext i3 %x to i16
+  %C = lshr i16 %B, 13
+  %D = trunc i16 %C to i8
+  ret i8 %D
+}