[InstCombine] Don't sink an instr after a catchswitch

A catchswitch is a terminator, instructions cannot be inserted after it.

llvm-svn: 265158

2 files changed, 50 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 8f7fd2e1bb6..3eebf5b9487 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -2724,12 +2724,15 @@ static bool TryToSinkInstruction(Instruction *I, BasicBlock *DestBlock) {
         &DestBlock->getParent()->getEntryBlock())
     return false;
 
+  // Do not sink into catchswitch blocks.
+  if (isa<CatchSwitchInst>(DestBlock->getTerminator()))
+    return false;
+
   // Do not sink convergent call instructions.
   if (auto *CI = dyn_cast<CallInst>(I)) {
     if (CI->isConvergent())
       return false;
   }
-
   // We can only sink load instructions if there is nothing between the load and
   // the end of block that could change the value.
   if (I->mayReadFromMemory()) {
@@ -2823,6 +2826,7 @@ bool InstCombiner::run() {
         if (UserIsSuccessor && UserParent->getSinglePredecessor()) {
           // Okay, the CFG is simple enough, try to sink this instruction.
           if (TryToSinkInstruction(I, UserParent)) {
+            DEBUG(dbgs() << "IC: Sink: " << *I << '\n');
             MadeIRChange = true;
             // We'll add uses of the sunk instruction below, but since sinking
             // can expose opportunities for it's *operands* add them to the
diff --git a/llvm/test/Transforms/InstCombine/sink-into-catchswitch.ll b/llvm/test/Transforms/InstCombine/sink-into-catchswitch.ll
new file mode 100644
index 00000000000..04a62250fc5
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/sink-into-catchswitch.ll
@@ -0,0 +1,45 @@
+; RUN: opt -instcombine -S < %s | FileCheck %s
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc18.0.0"
+
+%struct.B = type { i64, i64 }
+
+define void @test1(%struct.B* %p) personality i32 (...)* @__CxxFrameHandler3 {
+invoke.cont:
+  %0 = bitcast %struct.B* %p to <2 x i64>*
+  %1 = load <2 x i64>, <2 x i64>* %0, align 8
+  %2 = extractelement <2 x i64> %1, i32 0
+  invoke void @throw()
+          to label %unreachable unwind label %catch.dispatch
+
+catch.dispatch:                                   ; preds = %invoke.cont
+  %cs = catchswitch within none [label %invoke.cont1] unwind label %ehcleanup
+
+invoke.cont1:                                     ; preds = %catch.dispatch
+  %catch = catchpad within %cs [i8* null, i32 64, i8* null]
+  invoke void @throw() [ "funclet"(token %catch) ]
+          to label %unreachable unwind label %ehcleanup
+
+ehcleanup:                                        ; preds = %invoke.cont1, %catch.dispatch
+  %phi = phi i64 [ %2, %catch.dispatch ], [ 9, %invoke.cont1 ]
+  %cleanup = cleanuppad within none []
+  call void @release(i64 %phi) [ "funclet"(token %cleanup) ]
+  cleanupret from %cleanup unwind to caller
+
+unreachable:                                      ; preds = %invoke.cont1, %invoke.cont
+  unreachable
+}
+
+; CHECK-LABEL: define void @test1(
+; CHECK: %[[bc:.*]] = bitcast %struct.B* %p to <2 x i64>*
+; CHECK: %[[ld:.*]] = load <2 x i64>, <2 x i64>* %[[bc]], align 8
+; CHECK: %[[ee:.*]] = extractelement <2 x i64> %[[ld]], i32 0
+
+; CHECK: %[[phi:.*]] = phi i64 [ %[[ee]], {{.*}} ], [ 9, {{.*}} ]
+; CHECK: call void @release(i64 %[[phi]])
+
+declare i32 @__CxxFrameHandler3(...)
+
+declare void @throw()
+
+declare void @release(i64)