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Differential D27493

[GVNHoist] Invalidate MemDep when an instruction is moved.
ClosedPublic

Authored by efriedma on Dec 6 2016, 4:50 PM.

Details

Reviewers
sebpop
hiraditya
Commits
rGc6885fc36994: [GVNHoist] Invalidate MemDep when an instruction is moved.
rL288968: [GVNHoist] Invalidate MemDep when an instruction is moved.
Summary

See also r279907.

Fixes https://llvm.org/bugs/show_bug.cgi?id=30991 .

Diff Detail

Repository
rL LLVM

Event Timeline

efriedma updated this revision to Diff 80507.Dec 6 2016, 4:50 PM
efriedma retitled this revision from to [GVNHoist] Invalidate MemDep when an instruction is moved..
efriedma updated this object.
efriedma added reviewers: hiraditya, sebpop.
efriedma set the repository for this revision to rL LLVM.
efriedma added a subscriber: llvm-commits.
sebpop accepted this revision.Dec 6 2016, 6:20 PM
sebpop edited edge metadata.

LGTM. Thanks!

This revision is now accepted and ready to land.Dec 6 2016, 6:20 PM
Closed by commit rL288968: [GVNHoist] Invalidate MemDep when an instruction is moved. (authored by efriedma). · Explain WhyDec 7 2016, 12:07 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
trunk/
lib/
Transforms/
Scalar/
1 line
test/
Transforms/
GVNHoist/
33 lines

Diff 80639

llvm/trunk/lib/Transforms/Scalar/GVNHoist.cpp

Show First 20 Lines • Show All 796 Lines • ▼ Show 20 Lines for (const HoistingPointInfo &HP : HPL) {
// When not HoistingGeps we need to copy the GEPs. // When not HoistingGeps we need to copy the GEPs.
if (!makeGepOperandsAvailable(Repl, HoistPt, InstructionsToHoist)) if (!makeGepOperandsAvailable(Repl, HoistPt, InstructionsToHoist))
continue; continue;
} }
// Move the instruction at the end of HoistPt. // Move the instruction at the end of HoistPt.
Instruction *Last = HoistPt->getTerminator(); Instruction *Last = HoistPt->getTerminator();
MD->removeInstruction(Repl);
Repl->moveBefore(Last); Repl->moveBefore(Last);
DFSNumber[Repl] = DFSNumber[Last]++; DFSNumber[Repl] = DFSNumber[Last]++;
} }
MemoryAccess *NewMemAcc = MSSA->getMemoryAccess(Repl); MemoryAccess *NewMemAcc = MSSA->getMemoryAccess(Repl);
if (MoveAccess) { if (MoveAccess) {
▲ Show 20 Lines • Show All 201 Lines • Show Last 20 Lines

llvm/trunk/test/Transforms/GVNHoist/hoist.ll

Show First 20 Lines • Show All 705 Lines • ▼ Show 20 Lines
return: ; preds = %if.end, %if.then return: ; preds = %if.end, %if.then
%retval.0 = phi i32 [ %l1, %if.then ], [ %l2, %if.end ] %retval.0 = phi i32 [ %l1, %if.then ], [ %l2, %if.end ]
ret i32 %retval.0 ret i32 %retval.0
} }
; CHECK-LABEL: define i32 @mergeAlignments( ; CHECK-LABEL: define i32 @mergeAlignments(
; CHECK: %[[load:.*]] = load i32, i32* %y, align 1 ; CHECK: %[[load:.*]] = load i32, i32* %y, align 1
; CHECK: %[[phi:.*]] = phi i32 [ %[[load]], %{{.*}} ], [ %[[load]], %{{.*}} ] ; CHECK: %[[phi:.*]] = phi i32 [ %[[load]], %{{.*}} ], [ %[[load]], %{{.*}} ]
; CHECK: i32 %[[phi]] ; CHECK: i32 %[[phi]]
declare i8 @pr30991_f() nounwind readonly
declare void @pr30991_f1(i8)
define i8 @pr30991(i8* %sp, i8* %word, i1 %b1, i1 %b2) {
entry:
br i1 %b1, label %a, label %b
a:
%r0 = load i8, i8* %word, align 1
%incdec.ptr = getelementptr i8, i8* %sp, i32 1
%rr0 = call i8 @pr30991_f() nounwind readonly
call void @pr30991_f1(i8 %r0)
ret i8 %rr0
b:
br i1 %b2, label %c, label %x
c:
%r1 = load i8, i8* %word, align 1
%incdec.ptr115 = getelementptr i8, i8* %sp, i32 1
%rr1 = call i8 @pr30991_f() nounwind readonly
call void @pr30991_f1(i8 %r1)
ret i8 %rr1
x:
%r2 = load i8, i8* %word, align 1
ret i8 %r2
}
; CHECK-LABEL: define i8 @pr30991
; CHECK: %r0 = load i8, i8* %word, align 1
; CHECK-NEXT: br i1 %b1, label %a, label %b