[NFC] Switch a few uses of undef to poison as placeholders for unreachble code

diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
index a8c39f8..e977dd1 100644 (file)
--- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -382,7 +382,7 @@ bool IndVarSimplify::handleFloatingPointIV(Loop *L, PHINode *PN) {
   RecursivelyDeleteTriviallyDeadInstructions(Compare, TLI, MSSAU.get());
 
   // Delete the old floating point increment.
-  Incr->replaceAllUsesWith(UndefValue::get(Incr->getType()));
+  Incr->replaceAllUsesWith(PoisonValue::get(Incr->getType()));
   RecursivelyDeleteTriviallyDeadInstructions(Incr, TLI, MSSAU.get());
 
   // If the FP induction variable still has uses, this is because something else

diff --git a/llvm/lib/Transforms/Scalar/LoopDeletion.cpp b/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
index 66d452f..93f3cd7 100644 (file)
--- a/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
@@ -458,13 +458,13 @@ static LoopDeletionResult deleteLoopIfDead(Loop *L, DominatorTree &DT,
   if (ExitBlock && isLoopNeverExecuted(L)) {
     LLVM_DEBUG(dbgs() << "Loop is proven to never execute, delete it!");
     // We need to forget the loop before setting the incoming values of the exit
-    // phis to undef, so we properly invalidate the SCEV expressions for those
+    // phis to poison, so we properly invalidate the SCEV expressions for those
     // phis.
     SE.forgetLoop(L);
-    // Set incoming value to undef for phi nodes in the exit block.
+    // Set incoming value to poison for phi nodes in the exit block.
     for (PHINode &P : ExitBlock->phis()) {
       std::fill(P.incoming_values().begin(), P.incoming_values().end(),
-                UndefValue::get(P.getType()));
+                PoisonValue::get(P.getType()));
     }
     ORE.emit([&]() {
       return OptimizationRemark(DEBUG_TYPE, "NeverExecutes", L->getStartLoc(),

diff --git a/llvm/lib/Transforms/Scalar/Scalarizer.cpp b/llvm/lib/Transforms/Scalar/Scalarizer.cpp
index 8a5c988..08f4b21 100644 (file)
--- a/llvm/lib/Transforms/Scalar/Scalarizer.cpp
+++ b/llvm/lib/Transforms/Scalar/Scalarizer.cpp
@@ -400,7 +400,7 @@ Scatterer ScalarizerVisitor::scatter(Instruction *Point, Value *V,
     // need to analyse them further.
     if (!DT->isReachableFromEntry(VOp->getParent()))
       return Scatterer(Point->getParent(), Point->getIterator(),
-                       UndefValue::get(V->getType()), PtrElemTy);
+                       PoisonValue::get(V->getType()), PtrElemTy);
     // Put the scattered form of an instruction directly after the
     // instruction, skipping over PHI nodes and debug intrinsics.
     BasicBlock *BB = VOp->getParent();

diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index e37d7c0..0535608 100644 (file)
--- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -1684,7 +1684,7 @@ deleteDeadBlocksFromLoop(Loop &L,
     // uses in other blocks.
     for (auto &I : *BB)
       if (!I.use_empty())
-        I.replaceAllUsesWith(UndefValue::get(I.getType()));
+        I.replaceAllUsesWith(PoisonValue::get(I.getType()));
     BB->dropAllReferences();
   }
 

diff --git a/llvm/test/Transforms/LoopDeletion/unreachable-loops.ll b/llvm/test/Transforms/LoopDeletion/unreachable-loops.ll
index bd0d53f..ff37be2 100644 (file)
--- a/llvm/test/Transforms/LoopDeletion/unreachable-loops.ll
+++ b/llvm/test/Transforms/LoopDeletion/unreachable-loops.ll
@@ -79,7 +79,7 @@ define i64 @test3(i64 %n, i64 %m, i64 %maybe_zero) nounwind {
 ; CHECK:       bb.preheader:
 ; CHECK-NEXT:    br label [[RETURN_LOOPEXIT:%.*]]
 ; CHECK:       return.loopexit:
-; CHECK-NEXT:    [[X_LCSSA_PH:%.*]] = phi i64 [ undef, [[BB_PREHEADER]] ]
+; CHECK-NEXT:    [[X_LCSSA_PH:%.*]] = phi i64 [ poison, [[BB_PREHEADER]] ]
 ; CHECK-NEXT:    br label [[RETURN]]
 ; CHECK:       return:
 ; CHECK-NEXT:    [[X_LCSSA:%.*]] = phi i64 [ 20, [[ENTRY:%.*]] ], [ [[X_LCSSA_PH]], [[RETURN_LOOPEXIT]] ]
@@ -244,7 +244,7 @@ define i64 @test7(i64 %n) {
 ; CHECK:       L2.preheader:
 ; CHECK-NEXT:    br label [[L1LATCH_LOOPEXIT:%.*]]
 ; CHECK:       L1Latch.loopexit:
-; CHECK-NEXT:    [[Y_L2_LCSSA:%.*]] = phi i64 [ undef, [[L2_PREHEADER]] ]
+; CHECK-NEXT:    [[Y_L2_LCSSA:%.*]] = phi i64 [ poison, [[L2_PREHEADER]] ]
 ; CHECK-NEXT:    br label [[L1LATCH]]
 ; CHECK:       L1Latch:
 ; CHECK-NEXT:    [[Y:%.*]] = phi i64 [ [[Y_NEXT]], [[L1]] ], [ [[Y_L2_LCSSA]], [[L1LATCH_LOOPEXIT]] ]
@@ -430,7 +430,7 @@ define i64 @test12(i64 %n){
 ; CHECK:       exit1:
 ; CHECK-NEXT:    ret i64 42
 ; CHECK:       exit:
-; CHECK-NEXT:    [[Y_PHI:%.*]] = phi i64 [ undef, [[L1_PREHEADER]] ]
+; CHECK-NEXT:    [[Y_PHI:%.*]] = phi i64 [ poison, [[L1_PREHEADER]] ]
 ; CHECK-NEXT:    ret i64 [[Y_PHI]]
 ;
 ; REMARKS-LABEL: Function: test12
@@ -470,7 +470,7 @@ define i64 @test13(i64 %n) {
 ; CHECK:       exit1:
 ; CHECK-NEXT:    ret i64 42
 ; CHECK:       exit:
-; CHECK-NEXT:    [[Y_PHI:%.*]] = phi i64 [ undef, [[L1_PREHEADER]] ]
+; CHECK-NEXT:    [[Y_PHI:%.*]] = phi i64 [ poison, [[L1_PREHEADER]] ]
 ; CHECK-NEXT:    ret i64 [[Y_PHI]]
 ;
 ; REMARKS-LABEL: Function: test13

diff --git a/llvm/test/Transforms/LoopDeletion/update-scev.ll b/llvm/test/Transforms/LoopDeletion/update-scev.ll
index 56cc263..71078d8 100644 (file)
--- a/llvm/test/Transforms/LoopDeletion/update-scev.ll
+++ b/llvm/test/Transforms/LoopDeletion/update-scev.ll
@@ -7,7 +7,7 @@
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.11.0"
 
-define void @pr27570() {
+define void @pr27570(i1 %c1) {
 ; IR-AFTER-TRANSFORM-LABEL: @pr27570(
 entry:
   br label %for.cond
@@ -52,7 +52,7 @@ for.inc11:                                        ; preds = %for.body6
   br i1 %tobool, label %for.cond14, label %for.body
 
 for.cond14:                                       ; preds = %for.cond14, %for.inc11
-  br i1 undef, label %for.cond, label %for.cond14
+  br i1 %c1, label %for.cond, label %for.cond14
 }
 
 declare void @sideeffect(i32)
@@ -65,7 +65,7 @@ define void @test2(double* %bx, i64 %by) local_unnamed_addr align 2 {
 ; IR-AFTER-TRANSFORM-NOT: for.body7.1:
 
 ; SCEV-EXPRS-LABEL: test2
-; SCEV-EXPRS:     %inc.lcssa.1 = phi i64 [ undef, %for.body7.preheader.1 ]
+; SCEV-EXPRS:     %inc.lcssa.1 = phi i64 [ poison, %for.body7.preheader.1 ]
 ; SCEV-EXPRS-NEXT: -->  undef
 entry:
   %cmp = icmp sgt i64 %by, 0

diff --git a/llvm/test/Transforms/Scalarizer/phi-unreachable-pred.ll b/llvm/test/Transforms/Scalarizer/phi-unreachable-pred.ll
index b0df800..d700858 100644 (file)
--- a/llvm/test/Transforms/Scalarizer/phi-unreachable-pred.ll
+++ b/llvm/test/Transforms/Scalarizer/phi-unreachable-pred.ll
@@ -11,8 +11,8 @@ define i16 @f1() {
 ; CHECK:       for.cond:
 ; CHECK-NEXT:    br i1 undef, label [[FOR_BODY:%.*]], label [[FOR_END]]
 ; CHECK:       for.end:
-; CHECK-NEXT:    [[EXTRACT:%.*]] = phi i16 [ 1, [[ENTRY:%.*]] ], [ undef, [[FOR_COND]] ]
-; CHECK-NEXT:    ret i16 [[EXTRACT]]
+; CHECK-NEXT:    [[PHI_I0:%.*]] = phi i16 [ 1, [[ENTRY:%.*]] ], [ poison, [[FOR_COND]] ]
+; CHECK-NEXT:    ret i16 [[PHI_I0]]
 ;
 entry:
   br label %for.end
@@ -53,8 +53,8 @@ define void @f2() {
 ; CHECK:       for.cond1.for.end7_crit_edge:
 ; CHECK-NEXT:    br label [[IF_END8]]
 ; CHECK:       if.end8:
-; CHECK-NEXT:    [[E_SROA_3_4_I0:%.*]] = phi i64 [ undef, [[FOR_BODY]] ], [ undef, [[FOR_COND1_FOR_END7_CRIT_EDGE]] ], [ undef, [[IF_THEN]] ]
-; CHECK-NEXT:    [[E_SROA_3_4_I1:%.*]] = phi i64 [ undef, [[FOR_BODY]] ], [ undef, [[FOR_COND1_FOR_END7_CRIT_EDGE]] ], [ undef, [[IF_THEN]] ]
+; CHECK-NEXT:    [[E_SROA_3_4_I0:%.*]] = phi i64 [ undef, [[FOR_BODY]] ], [ poison, [[FOR_COND1_FOR_END7_CRIT_EDGE]] ], [ undef, [[IF_THEN]] ]
+; CHECK-NEXT:    [[E_SROA_3_4_I1:%.*]] = phi i64 [ undef, [[FOR_BODY]] ], [ poison, [[FOR_COND1_FOR_END7_CRIT_EDGE]] ], [ undef, [[IF_THEN]] ]
 ; CHECK-NEXT:    br label [[FOR_BODY]]
 ;
 entry: