Do not let dbg intrinsic block folding of two entry phi node.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63671 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index d891eeb..9f5df98 100644 (file)
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -15,6 +15,7 @@
 #include "llvm/Transforms/Utils/Local.h"
 #include "llvm/Constants.h"
 #include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
 #include "llvm/Type.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Support/CFG.h"
@@ -1262,7 +1263,7 @@ static bool FoldTwoEntryPHINode(PHINode *PN) {
     DomBlock = *pred_begin(Pred);
     for (BasicBlock::iterator I = Pred->begin();
          !isa<TerminatorInst>(I); ++I)
-      if (!AggressiveInsts.count(I)) {
+      if (!AggressiveInsts.count(I) && !isa<DbgInfoIntrinsic>(I)) {
         // This is not an aggressive instruction that we can promote.
         // Because of this, we won't be able to get rid of the control
         // flow, so the xform is not worth it.
@@ -1276,7 +1277,7 @@ static bool FoldTwoEntryPHINode(PHINode *PN) {
     DomBlock = *pred_begin(Pred);
     for (BasicBlock::iterator I = Pred->begin();
          !isa<TerminatorInst>(I); ++I)
-      if (!AggressiveInsts.count(I)) {
+      if (!AggressiveInsts.count(I) && !isa<DbgInfoIntrinsic>(I)) {
         // This is not an aggressive instruction that we can promote.
         // Because of this, we won't be able to get rid of the control
         // flow, so the xform is not worth it.

diff --git a/test/Transforms/SimplifyCFG/two-entry-phi-return.dbg.ll b/test/Transforms/SimplifyCFG/two-entry-phi-return.dbg.ll
new file mode 100644 (file)
index 0000000..62d4a43
--- /dev/null
+++ b/test/Transforms/SimplifyCFG/two-entry-phi-return.dbg.ll
@@ -0,0 +1,28 @@
+; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis | not grep br
+
+        %llvm.dbg.anchor.type = type { i32, i32 }
+        %llvm.dbg.compile_unit.type = type { i32, { }*, i32, i8*, i8*, i8*, i1, i1, i8* }
+
+@llvm.dbg.compile_units = linkonce constant %llvm.dbg.anchor.type { i32 458752, i32 17 }, section "llvm.metadata"              ; 
+
+@.str = internal constant [4 x i8] c"a.c\00", section "llvm.metadata"          ; <[4 x i8]*> [#uses=1]
+@.str1 = internal constant [6 x i8] c"/tmp/\00", section "llvm.metadata"       ; <[6 x i8]*> [#uses=1]
+@.str2 = internal constant [55 x i8] c"4.2.1 (Based on Apple Inc. build 5636) (LLVM build 00)\00", section "llvm.metadata"             ; <[55 x i8]*> [#uses=1]
+@llvm.dbg.compile_unit = internal constant %llvm.dbg.compile_unit.type { i32 458769, { }* bitcast (%llvm.dbg.anchor.type* @llvm.dbg.compile_units to { }*), i32 1, i8* getelementptr ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr ([6 x i8]* @.str1, i32 0, i32 0), i8* getelementptr ([55 x i8]* @.str2, i32 0, i32 0), i1 true, i1 false, i8* null }, section "llvm.metadata"          ; <%llvm.dbg.compile_unit.type*> [#uses=1]
+
+declare void @llvm.dbg.stoppoint(i32, i32, { }*) nounwind
+
+define i1 @qux(i8* %m, i8* %n, i8* %o, i8* %p) nounwind  {
+entry:
+        %tmp7 = icmp eq i8* %m, %n
+        br i1 %tmp7, label %bb, label %UnifiedReturnBlock
+
+bb:
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        %tmp15 = icmp eq i8* %o, %p
+        br label %UnifiedReturnBlock
+
+UnifiedReturnBlock:
+        %result = phi i1 [ 0, %entry ], [ %tmp15, %bb ]
+        ret i1 %result
+}