[LoopStrengthReduce] Don't hoist into a catchswitch

We try to hoist the insertion point as high as possible to encourage
sharing.  However, we must be careful not to hoist into a catchswitch as
it is both an EHPad and a terminator.

llvm-svn: 264344
This commit is contained in:
David Majnemer 2016-03-24 21:40:22 +00:00
parent 3cf9ff12c5
commit e09d035dad
2 changed files with 56 additions and 1 deletions

View File

@ -4353,6 +4353,11 @@ LSRInstance::HoistInsertPosition(BasicBlock::iterator IP,
bool AllDominate = true;
Instruction *BetterPos = nullptr;
Instruction *Tentative = IDom->getTerminator();
// Don't bother attempting to insert before a catchswitch, their basic block
// cannot have other non-PHI instructions.
if (isa<CatchSwitchInst>(Tentative))
return IP;
for (Instruction *Inst : Inputs) {
if (Inst == Tentative || !DT.dominates(Inst, Tentative)) {
AllDominate = false;
@ -4426,7 +4431,7 @@ LSRInstance::AdjustInsertPositionForExpand(BasicBlock::iterator LowestIP,
while (isa<PHINode>(IP)) ++IP;
// Ignore landingpad instructions.
while (!isa<TerminatorInst>(IP) && IP->isEHPad()) ++IP;
while (IP->isEHPad()) ++IP;
// Ignore debug intrinsics.
while (isa<DbgInfoIntrinsic>(IP)) ++IP;

View File

@ -0,0 +1,50 @@
; 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-msvc18.0.0"
%struct.L = type { i8, i8* }
declare i32 @__CxxFrameHandler3(...)
@GV1 = external global %struct.L*
@GV2 = external global %struct.L
define void @b_copy_ctor() personality i32 (...)* @__CxxFrameHandler3 {
entry:
%0 = load %struct.L*, %struct.L** @GV1, align 8
br label %for.cond
for.cond: ; preds = %call.i.noexc, %entry
%d.0 = phi %struct.L* [ %0, %entry ], [ %incdec.ptr, %call.i.noexc ]
invoke void @a_copy_ctor()
to label %call.i.noexc unwind label %catch.dispatch
call.i.noexc: ; preds = %for.cond
%incdec.ptr = getelementptr inbounds %struct.L, %struct.L* %d.0, i64 1
br label %for.cond
catch.dispatch: ; preds = %for.cond
%1 = catchswitch within none [label %catch] unwind to caller
catch: ; preds = %catch.dispatch
%2 = catchpad within %1 [i8* null, i32 64, i8* null]
%cmp16 = icmp eq %struct.L* %0, %d.0
br i1 %cmp16, label %for.end, label %for.body
for.body: ; preds = %for.body, %catch
%cmp = icmp eq %struct.L* @GV2, %d.0
br i1 %cmp, label %for.end, label %for.body
for.end: ; preds = %for.body, %catch
catchret from %2 to label %try.cont
try.cont: ; preds = %for.end
ret void
}
; CHECK-LABEL: define void @b_copy_ctor(
; CHECK: catchpad
; CHECK-NEXT: icmp eq %struct.L
; CHECK-NEXT: getelementptr {{.*}} i64 sub (i64 0, i64 ptrtoint (%struct.L* @GV2 to i64))
declare void @a_copy_ctor()