Ignore dbg intrinsics while propagating conditional expression info.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63876 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Transforms/Utils/Local.h b/include/llvm/Transforms/Utils/Local.h
index 35d2c0ce7e033cf74b095781dc34f15a394290ae..2032d548714abe87b38f340eaf6d5f708f6fe307 100644 (file)
--- a/include/llvm/Transforms/Utils/Local.h
+++ b/include/llvm/Transforms/Utils/Local.h
@@ -39,6 +39,14 @@ template<typename T> class SmallVectorImpl;
 ///
 bool ConstantFoldTerminator(BasicBlock *BB);
 
+//===----------------------------------------------------------------------===//
+//  CFG Simplification
+//
+
+/// isTerminatorFirstRelevantInsn - Return true if Term is very first 
+/// instruction ignoring Phi nodes and dbg intrinsics.
+bool isTerminatorFirstRelevantInsn(BasicBlock *BB, Instruction *Term);
+
 //===----------------------------------------------------------------------===//
 //  Local dead code elimination.
 //

diff --git a/lib/Transforms/Scalar/CondPropagate.cpp b/lib/Transforms/Scalar/CondPropagate.cpp
index f68fb292e4a909a70d59ec41a14628f0f484ca47..1b755171c318e42254c28398267d563f4b1faa3b 100644 (file)
--- a/lib/Transforms/Scalar/CondPropagate.cpp
+++ b/lib/Transforms/Scalar/CondPropagate.cpp
@@ -137,7 +137,7 @@ void CondProp::SimplifyPredecessors(BranchInst *BI) {
   if (!PN->hasOneUse()) return;
 
   BasicBlock *BB = BI->getParent();
-  if (&*BB->begin() != PN || &*next(BB->begin()) != BI)
+  if (!isTerminatorFirstRelevantInsn (BB, BI))
     return;
 
   // Ok, we have this really simple case, walk the PHI operands, looking for
@@ -171,7 +171,7 @@ void CondProp::SimplifyPredecessors(SwitchInst *SI) {
   if (!PN->hasOneUse()) return;
 
   BasicBlock *BB = SI->getParent();
-  if (&*BB->begin() != PN || &*next(BB->begin()) != SI)
+  if (!isTerminatorFirstRelevantInsn (BB, SI))
     return;
 
   bool RemovedPreds = false;

diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index c22485342e09cd543eaaf0a7c8625ff1e93fea1c..aa6efe80b32f25f82821172b321832200c7f480f 100644 (file)
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -148,6 +148,23 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB) {
   return false;
 }
 
+//===----------------------------------------------------------------------===//
+//  CFG Simplification
+//
+
+/// isTerminatorFirstRelevantInsn - Return true if Term is very first 
+/// instruction ignoring Phi nodes and dbg intrinsics.
+bool llvm::isTerminatorFirstRelevantInsn(BasicBlock *BB, Instruction *Term) {
+  BasicBlock::iterator BBI = Term;
+  while (BBI != BB->begin()) {
+    --BBI;
+    if (!isa<DbgInfoIntrinsic>(BBI))
+      break;
+  }
+  if (isa<PHINode>(BBI) || &*BBI == Term)
+    return true;
+  return false;
+}
 
 //===----------------------------------------------------------------------===//
 //  Local dead code elimination...

diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index d9c4b69e6de0f6cd9648ff0fdef42f028d5d9405..0248d3d0ca092cf84cdad1633830411a79fdc541 100644 (file)
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1330,20 +1330,6 @@ static bool FoldTwoEntryPHINode(PHINode *PN) {
   return true;
 }
 
-/// isTerminatorFirstRelevantInsn - Return true if Term is very first 
-/// instruction ignoring Phi nodes and dbg intrinsics.
-static bool isTerminatorFirstRelevantInsn(BasicBlock *BB, Instruction *Term) {
-  BasicBlock::iterator BBI = Term;
-  while (BBI != BB->begin()) {
-    --BBI;
-    if (!isa<DbgInfoIntrinsic>(BBI))
-      break;
-  }
-  if (isa<PHINode>(BBI) || &*BBI == Term)
-    return true;
-  return false;
-}
-
 /// SimplifyCondBranchToTwoReturns - If we found a conditional branch that goes
 /// to two returning blocks, try to merge them together into one return,
 /// introducing a select if the return values disagree.

diff --git a/test/Transforms/CondProp/basictest-dbg.ll b/test/Transforms/CondProp/basictest-dbg.ll
new file mode 100644 (file)
index 0000000..d8a680b
--- /dev/null
+++ b/test/Transforms/CondProp/basictest-dbg.ll
@@ -0,0 +1,45 @@
+; RUN: llvm-as < %s | opt -condprop | llvm-dis | \
+; RUN:    not grep {br label}
+
+        %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 i32 @test(i1 %C) {
+        br i1 %C, label %T1, label %F1
+
+T1:             ; preds = %0
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        br label %Cont
+
+F1:             ; preds = %0
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        br label %Cont
+
+Cont:           ; preds = %F1, %T1
+        %C2 = phi i1 [ false, %F1 ], [ true, %T1 ]              ; <i1> [#uses=1]
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        br i1 %C2, label %T2, label %F2
+
+T2:             ; preds = %Cont
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        call void @bar( )
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        ret i32 17
+
+F2:             ; preds = %Cont
+call void @llvm.dbg.stoppoint(i32 5, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*))
+        ret i32 1
+}
+
+declare void @bar()
+