[llvm] 88c2454 - [InstCombine] Add PR38929 test case

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2021-04-06T14:42:30+01:00
New Revision: 88c2454057b6cd1b122f7fadde666e6b8ea6ebd3

URL: https://github.com/llvm/llvm-project/commit/88c2454057b6cd1b122f7fadde666e6b8ea6ebd3
DIFF: https://github.com/llvm/llvm-project/commit/88c2454057b6cd1b122f7fadde666e6b8ea6ebd3.diff

LOG: [InstCombine] Add PR38929 test case

Fold (~x & y) | ~(x | y) --> ~x

Added: 
    

Modified: 
    llvm/test/Transforms/InstCombine/or.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/InstCombine/or.ll b/llvm/test/Transforms/InstCombine/or.ll
index 22ba395ebe9f..33652f0e1619 100644
--- a/llvm/test/Transforms/InstCombine/or.ll
+++ b/llvm/test/Transforms/InstCombine/or.ll
@@ -4,8 +4,8 @@
 target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n32:64"
 declare void @use(i32)
 
+; Should be eliminated
 define i32 @test12(i32 %A) {
-        ; Should be eliminated
 ; CHECK-LABEL: @test12(
 ; CHECK-NEXT:    [[C:%.*]] = and i32 [[A:%.*]], 8
 ; CHECK-NEXT:    ret i32 [[C]]
@@ -1267,6 +1267,20 @@ end:
   ret i32 %conv8
 }
 
+; (~x & y) | ~(x | y) --> ~x
+define i32 @PR38929(i32 %0, i32 %1) {
+; CHECK-LABEL: @PR38929(
+; CHECK-NEXT:    [[TMP3:%.*]] = xor i32 [[TMP0:%.*]], -1
+; CHECK-NEXT:    ret i32 [[TMP3]]
+;
+  %3 = xor i32 %0, -1
+  %4 = and i32 %3, %1
+  %5 = or i32 %1, %0
+  %6 = xor i32 %5, -1
+  %7 = or i32 %4, %6
+  ret i32 %7
+}
+
 define i32 @test1(i32 %x, i32 %y) {
 ; CHECK-LABEL: @test1(
 ; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[Y:%.*]], [[X:%.*]]