[llvm] r291966 - [LoopStrengthReduce] Don't bother rewriting PHIs in catchswitch blocks

[Hans Wennborg via llvm-commits]

Merged in r292340.

Cheers,
Hans

On Fri, Jan 13, 2017 at 3:59 PM, David Majnemer
<david.majnemer at gmail.com> wrote:
> I think so.
>
> On Fri, Jan 13, 2017 at 3:59 PM, Hans Wennborg <hans at chromium.org> wrote:
>>
>> Should we merge this to the release branch?
>>
>> On Fri, Jan 13, 2017 at 2:24 PM, David Majnemer via llvm-commits
>> <llvm-commits at lists.llvm.org> wrote:
>> > Author: majnemer
>> > Date: Fri Jan 13 16:24:27 2017
>> > New Revision: 291966
>> >
>> > URL: http://llvm.org/viewvc/llvm-project?rev=291966&view=rev
>> > Log:
>> > [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.
>> >
>> > Added:
>> >     llvm/trunk/test/Transforms/LoopStrengthReduce/pr31627.ll
>> > Modified:
>> >     llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp
>> >
>> > Modified: llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp
>> > URL:
>> > http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp?rev=291966&r1=291965&r2=291966&view=diff
>> >
>> > ==============================================================================
>> > --- llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp (original)
>> > +++ llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp Fri Jan 13
>> > 16:24:27 2017
>> > @@ -3163,6 +3163,9 @@ LSRInstance::CollectLoopInvariantFixupsA
>> >          // 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
>> >        // 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()) {
>> >
>> > Added: llvm/trunk/test/Transforms/LoopStrengthReduce/pr31627.ll
>> > URL:
>> > http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopStrengthReduce/pr31627.ll?rev=291966&view=auto
>> >
>> > ==============================================================================
>> > --- llvm/trunk/test/Transforms/LoopStrengthReduce/pr31627.ll (added)
>> > +++ llvm/trunk/test/Transforms/LoopStrengthReduce/pr31627.ll Fri Jan 13
>> > 16:24:27 2017
>> > @@ -0,0 +1,58 @@
>> > +; 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*)
>> >
>> >
>> > _______________________________________________
>> > llvm-commits mailing list
>> > llvm-commits at lists.llvm.org
>> > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>
>