[llvm] b9d8719 - [NFC][SimplifyCFG] Add test for SimplifyCondBranchToTwoReturns() mishandling

[Roman Lebedev via llvm-commits]

Author: Roman Lebedev
Date: 2021-07-23T00:36:59+03:00
New Revision: b9d8719a04350c27eb5542f4da579a8ad62c8c0b

URL: https://github.com/llvm/llvm-project/commit/b9d8719a04350c27eb5542f4da579a8ad62c8c0b
DIFF: https://github.com/llvm/llvm-project/commit/b9d8719a04350c27eb5542f4da579a8ad62c8c0b.diff

LOG: [NFC][SimplifyCFG] Add test for SimplifyCondBranchToTwoReturns() mishandling

Added: 
    

Modified: 
    llvm/test/Transforms/SimplifyCFG/return-merge.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/SimplifyCFG/return-merge.ll b/llvm/test/Transforms/SimplifyCFG/return-merge.ll
index 0b7aede886fb..44c218399d54 100644
--- a/llvm/test/Transforms/SimplifyCFG/return-merge.ll
+++ b/llvm/test/Transforms/SimplifyCFG/return-merge.ll
@@ -1,5 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck --check-prefixes=CHECK %s
+; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck --check-prefixes=CHECK,NODUPRET %s
+; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -simplifycfg-dup-ret -S | FileCheck --check-prefixes=CHECK,DUPRET %s
 ; RUN: opt < %s -debugify -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck --check-prefixes=DBGINFO %s
 
 define i32 @test1(i1 %C) {
@@ -23,9 +24,12 @@ F:              ; preds = %entry
 }
 
 define void @test2(i1 %C) {
-; CHECK-LABEL: @test2(
-; CHECK-NEXT:  common.ret:
-; CHECK-NEXT:    ret void
+; NODUPRET-LABEL: @test2(
+; NODUPRET-NEXT:  common.ret:
+; NODUPRET-NEXT:    ret void
+;
+; DUPRET-LABEL: @test2(
+; DUPRET-NEXT:    ret void
 ;
 ; DBGINFO-LABEL: @test2(
 ; DBGINFO-NEXT:  common.ret:
@@ -39,3 +43,66 @@ F:              ; preds = %0
   ret void
 }
 
+declare void @sideeffect0()
+declare void @sideeffect1()
+declare void @sideeffect2()
+
+define i32 @test3(i1 %C0, i1 %C1, i32 %v0, i32 %v1, i32 %v2) {
+; NODUPRET-LABEL: @test3(
+; NODUPRET-NEXT:  entry:
+; NODUPRET-NEXT:    call void @sideeffect0()
+; NODUPRET-NEXT:    br i1 [[C0:%.*]], label [[T:%.*]], label [[F:%.*]]
+; NODUPRET:       T:
+; NODUPRET-NEXT:    call void @sideeffect1()
+; NODUPRET-NEXT:    [[SPEC_SELECT:%.*]] = select i1 [[C1:%.*]], i32 [[V0:%.*]], i32 [[V1:%.*]]
+; NODUPRET-NEXT:    ret i32 [[SPEC_SELECT]]
+; NODUPRET:       F:
+; NODUPRET-NEXT:    call void @sideeffect2()
+; NODUPRET-NEXT:    ret i32 [[V2:%.*]]
+;
+; DUPRET-LABEL: @test3(
+; DUPRET-NEXT:  entry:
+; DUPRET-NEXT:    call void @sideeffect0()
+; DUPRET-NEXT:    br i1 [[C0:%.*]], label [[T:%.*]], label [[F:%.*]]
+; DUPRET:       T:
+; DUPRET-NEXT:    call void @sideeffect1()
+; DUPRET-NEXT:    [[RETVAL:%.*]] = select i1 [[C1:%.*]], i32 [[V0:%.*]], i32 [[V1:%.*]]
+; DUPRET-NEXT:    ret i32 [[RETVAL]]
+; DUPRET:       F:
+; DUPRET-NEXT:    call void @sideeffect2()
+; DUPRET-NEXT:    ret i32 [[V2:%.*]]
+;
+; DBGINFO-LABEL: @test3(
+; DBGINFO-NEXT:  entry:
+; DBGINFO-NEXT:    call void @sideeffect0(), !dbg [[DBG21:![0-9]+]]
+; DBGINFO-NEXT:    br i1 [[C0:%.*]], label [[T:%.*]], label [[F:%.*]], !dbg [[DBG22:![0-9]+]]
+; DBGINFO:       T:
+; DBGINFO-NEXT:    call void @sideeffect1(), !dbg [[DBG23:![0-9]+]]
+; DBGINFO-NEXT:    [[SPEC_SELECT:%.*]] = select i1 [[C1:%.*]], i32 [[V0:%.*]], i32 [[V1:%.*]], !dbg [[DBG24:![0-9]+]]
+; DBGINFO-NEXT:    ret i32 [[SPEC_SELECT]], !dbg [[DBG24]]
+; DBGINFO:       F:
+; DBGINFO-NEXT:    call void @sideeffect2(), !dbg [[DBG25:![0-9]+]]
+; DBGINFO-NEXT:    call void @llvm.dbg.value(metadata i32 [[V2:%.*]], metadata [[META20:![0-9]+]], metadata !DIExpression()), !dbg [[DBG26:![0-9]+]]
+; DBGINFO-NEXT:    ret i32 [[V2]], !dbg [[DBG27:![0-9]+]]
+;
+entry:
+  call void @sideeffect0()
+  br i1 %C0, label %T, label %F
+
+T.cont:
+  ; empty block with single predecessor
+  br label %end
+
+end:
+  %r = phi i32 [ %v0, %T.cont ], [ %v1, %T ], [ %v2, %F ]
+  ; empty block
+  ret i32 %r
+
+T:
+  call void @sideeffect1()
+  br i1 %C1, label %T.cont, label %end
+
+F:
+  call void @sideeffect2()
+  br label %end
+}