Revert rev. 63876. It is causing llvm-gcc bootstrap failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63888 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Transforms/Utils/Local.h

@@ -39,14 +39,6 @@ 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.
 //

lib/Transforms/Scalar/CondPropagate.cpp

@@ -148,7 +148,7 @@ void CondProp::SimplifyPredecessors(BranchInst *BI) {
   if (!PN->hasOneUse()) return;
 
   BasicBlock *BB = BI->getParent();
-  if (!isTerminatorFirstRelevantInsn (BB, BI))
+  if (&*BB->begin() != PN || &*next(BB->begin()) != BI)
     return;
 
   // Ok, we have this really simple case, walk the PHI operands, looking for
@@ -182,7 +182,7 @@ void CondProp::SimplifyPredecessors(SwitchInst *SI) {
   if (!PN->hasOneUse()) return;
 
   BasicBlock *BB = SI->getParent();
-  if (!isTerminatorFirstRelevantInsn (BB, SI))
+  if (&*BB->begin() != PN || &*next(BB->begin()) != SI)
     return;
 
   bool RemovedPreds = false;

lib/Transforms/Utils/Local.cpp

@@ -148,23 +148,6 @@ 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...

lib/Transforms/Utils/SimplifyCFG.cpp

@@ -1330,6 +1330,20 @@ 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.

test/Transforms/CondProp/basictest-dbg.ll

@@ -1,45 +0,0 @@
-; 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()
-