Commit f581e2cd authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r291966: 

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r291966 | majnemer | 2017-01-13 14:24:27 -0800 (Fri, 13 Jan 2017) | 6 lines

[LoopStrengthReduce] Don't bother rewriting PHIs in catchswitch blocks

The catchswitch instruction cannot be split, don't bother trying to
rewrite it.

This fixes PR31627.
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llvm-svn: 292340
parent 51d42e77

llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp

+5 −1
Original line number Diff line number Diff line
@@ -3163,6 +3163,9 @@ LSRInstance::CollectLoopInvariantFixupsAndFormulae() { 
        // Don't bother if the instruction is in a BB which ends in an EHPad.

        if (UseBB->getTerminator()->isEHPad())

          continue;

        // Don't bother rewriting PHIs in catchswitch blocks.

        if (isa<CatchSwitchInst>(UserInst->getParent()->getTerminator()))

          continue;

        // Ignore uses which are part of other SCEV expressions, to avoid

        // analyzing them multiple times.

        if (SE.isSCEVable(UserInst->getType())) {
@@ -4672,7 +4675,8 @@ void LSRInstance::RewriteForPHI(PHINode *PN, 
      // is the canonical backedge for this loop, which complicates post-inc

      // users.

      if (e != 1 && BB->getTerminator()->getNumSuccessors() > 1 &&

          !isa<IndirectBrInst>(BB->getTerminator())) {

          !isa<IndirectBrInst>(BB->getTerminator()) &&

          !isa<CatchSwitchInst>(BB->getTerminator())) {

        BasicBlock *Parent = PN->getParent();

        Loop *PNLoop = LI.getLoopFor(Parent);

        if (!PNLoop || Parent != PNLoop->getHeader()) {

llvm/test/Transforms/LoopStrengthReduce/pr31627.ll

0 → 100644
+58 −0
Original line number Diff line number Diff line 
; RUN: opt -S -loop-reduce < %s | FileCheck %s

target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"

target triple = "x86_64-pc-windows-msvc19.0.24215"



define void @fn3() personality i32 (...)* @__CxxFrameHandler3 {

entry:

  %call = invoke i32 @fn2()

          to label %for.cond.preheader unwind label %catch.dispatch2



for.cond.preheader:                               ; preds = %entry

  br label %for.cond



for.cond:                                         ; preds = %for.cond.preheader, %for.cond

  %b.0 = phi i32 [ %inc, %for.cond ], [ %call, %for.cond.preheader ]

  %inc = add nsw i32 %b.0, 1

  invoke void @fn1(i32 %inc)

          to label %for.cond unwind label %catch.dispatch



; CHECK:   %[[add:.*]] = add i32 %call, 1

; CHECK:   br label %for.cond



; CHECK: for.cond:                                         ; preds = %for.cond, %for.cond.preheader

; CHECK:   %[[lsr_iv:.*]] = phi i32 [ %lsr.iv.next, %for.cond ], [ %[[add]], %for.cond.preheader ]

; CHECK:   %[[lsr_iv_next:.*]] = add i32 %lsr.iv, 1

; CHECK:   invoke void @fn1(i32 %[[lsr_iv]])





catch.dispatch:                                   ; preds = %for.cond

  %0 = catchswitch within none [label %catch] unwind label %catch.dispatch2



catch:                                            ; preds = %catch.dispatch

  %1 = catchpad within %0 [i8* null, i32 64, i8* null]

  invoke void @_CxxThrowException(i8* null, i8* null) #2 [ "funclet"(token %1) ]

          to label %unreachable unwind label %catch.dispatch2



catch.dispatch2:                                  ; preds = %catch.dispatch, %catch, %entry

  %a.0 = phi i32 [ undef, %entry ], [ %call, %catch ], [ %call, %catch.dispatch ]

  %2 = catchswitch within none [label %catch3] unwind to caller



catch3:                                           ; preds = %catch.dispatch2

  %3 = catchpad within %2 [i8* null, i32 64, i8* null]

  call void @fn1(i32 %a.0) [ "funclet"(token %3) ]

  catchret from %3 to label %try.cont4



try.cont4:                                        ; preds = %catch3

  ret void



unreachable:                                      ; preds = %catch

  unreachable

}



declare i32 @fn2()



declare i32 @__CxxFrameHandler3(...)



declare void @fn1(i32)



declare void @_CxxThrowException(i8*, i8*)