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Differential D50009

[DebugInfo][LCSSA] Preserve debug location in lcssa phis
ClosedPublic

Authored by gramanas on Jul 30 2018, 1:29 PM.

Details

Reviewers
vsk
Commits
rGac3f8028da68: [DebugInfo][LCSSA] Preserve debug location in lcssa phis
rL338391: [DebugInfo][LCSSA] Preserve debug location in lcssa phis
Summary

When inserting lcssa Phi Nodes in the exit block
mak sure to preserve the original instructions DL.

Diff Detail

Event Timeline

gramanas created this revision.Jul 30 2018, 1:29 PM
Herald added subscribers: llvm-commits, JDevlieghere. · View Herald TranscriptJul 30 2018, 1:29 PM
Harbormaster completed remote builds in B20861: Diff 158059.Jul 30 2018, 1:30 PM
gbedwell added a subscriber: gbedwell.Jul 30 2018, 3:16 PM
vsk accepted this revision.Jul 30 2018, 3:54 PM

Thanks, LGTM.

This revision is now accepted and ready to land.Jul 30 2018, 3:54 PM
Closed by commit rL338391: [DebugInfo][LCSSA] Preserve debug location in lcssa phis (authored by gramanas). · Explain WhyJul 31 2018, 7:55 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
lib/
Transforms/
Utils/
3 lines
test/
Transforms/
LCSSA/
7 lines

Diff 158059

lib/Transforms/Utils/LCSSA.cpp

Show First 20 Lines • Show All 138 Lines • ▼ Show 20 Lines for (BasicBlock *ExitBB : ExitBlocks) {
continue; continue;
// If we already inserted something for this BB, don't reprocess it. // If we already inserted something for this BB, don't reprocess it.
if (SSAUpdate.HasValueForBlock(ExitBB)) if (SSAUpdate.HasValueForBlock(ExitBB))
continue; continue;
PHINode *PN = PHINode::Create(I->getType(), PredCache.size(ExitBB), PHINode *PN = PHINode::Create(I->getType(), PredCache.size(ExitBB),
I->getName() + ".lcssa", &ExitBB->front()); I->getName() + ".lcssa", &ExitBB->front());
// Get the debug location from the original instruction.
PN->setDebugLoc(I->getDebugLoc());
// Add inputs from inside the loop for this PHI. // Add inputs from inside the loop for this PHI.
for (BasicBlock *Pred : PredCache.get(ExitBB)) { for (BasicBlock *Pred : PredCache.get(ExitBB)) {
PN->addIncoming(I, Pred); PN->addIncoming(I, Pred);
// If the exit block has a predecessor not within the loop, arrange for // If the exit block has a predecessor not within the loop, arrange for
// the incoming value use corresponding to that predecessor to be // the incoming value use corresponding to that predecessor to be
// rewritten in terms of a different LCSSA PHI. // rewritten in terms of a different LCSSA PHI.
if (!L->contains(Pred)) if (!L->contains(Pred))
▲ Show 20 Lines • Show All 294 Lines • Show Last 20 Lines

test/Transforms/LCSSA/basictest.ll

; RUN: opt < %s -lcssa -S | FileCheck %s ; RUN: opt < %s -lcssa -S | FileCheck %s
; RUN: opt < %s -passes=lcssa -S | FileCheck %s ; RUN: opt < %s -passes=lcssa -S | FileCheck %s
; RUN: opt < %s -debugify -lcssa -S | FileCheck -check-prefix=CHECK2 %s ; RUN: opt < %s -debugify -lcssa -S | FileCheck -check-prefix=DEBUGIFY %s
define void @lcssa(i1 %S2) { define void @lcssa(i1 %S2) {
; CHECK-LABEL: @lcssa ; CHECK-LABEL: @lcssa
entry: entry:
br label %loop.interior br label %loop.interior
loop.interior: ; preds = %post.if, %entry loop.interior: ; preds = %post.if, %entry
br i1 %S2, label %if.true, label %if.false br i1 %S2, label %if.true, label %if.false
if.true: ; preds = %loop.interior if.true: ; preds = %loop.interior
%X1 = add i32 0, 0 ; <i32> [#uses=1] %X1 = add i32 0, 0 ; <i32> [#uses=1]
br label %post.if br label %post.if
if.false: ; preds = %loop.interior if.false: ; preds = %loop.interior
%X2 = add i32 0, 1 ; <i32> [#uses=1] %X2 = add i32 0, 1 ; <i32> [#uses=1]
br label %post.if br label %post.if
post.if: ; preds = %if.false, %if.true post.if: ; preds = %if.false, %if.true
%X3 = phi i32 [ %X1, %if.true ], [ %X2, %if.false ] ; <i32> [#uses=1] %X3 = phi i32 [ %X1, %if.true ], [ %X2, %if.false ] ; <i32> [#uses=1]
br i1 %S2, label %loop.exit, label %loop.interior br i1 %S2, label %loop.exit, label %loop.interior
loop.exit: ; preds = %post.if loop.exit: ; preds = %post.if
; CHECK: %X3.lcssa = phi i32 ; CHECK: %X3.lcssa = phi i32
; CHECK2: call void @llvm.dbg.value(metadata i32 %X3.lcssa ; DEBUGIFY: %X3.lcssa = phi i32 {{.*}}, !dbg ![[DbgLoc:[0-9]+]]
; DEBUGIFY-NEXT: call void @llvm.dbg.value(metadata i32 %X3.lcssa
; CHECK: %X4 = add i32 3, %X3.lcssa ; CHECK: %X4 = add i32 3, %X3.lcssa
%X4 = add i32 3, %X3 ; <i32> [#uses=0] %X4 = add i32 3, %X3 ; <i32> [#uses=0]
ret void ret void
} }
; Make sure the lcssa phi has %X3's debug location
; DEBUGIFY: ![[DbgLoc]] = !DILocation(line: 7