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Differential D9384

llvm.noalias - isPointerDereferenceable should look through them
ClosedPublic

Authored by hfinkel on Apr 30 2015, 8:35 AM.

Details

Reviewers
chandlerc
majnemer
Commits
rGbf3957a55381: Teach isDereferenceablePointer to look through returned-argument functions
rL275038: Teach isDereferenceablePointer to look through returned-argument functions
Summary

This is part of the series started by D9375, and teaches isPointerDereferenceable to look through calls to llvm.noalias.

Diff Detail

Event Timeline

hfinkel updated this revision to Diff 24718.Apr 30 2015, 8:35 AM
hfinkel retitled this revision from to llvm.noalias - isPointerDereferenceable should look through them.
hfinkel updated this object.
hfinkel edited the test plan for this revision. (Show Details)
hfinkel added reviewers: chandlerc, reames.
hfinkel added a subscriber: Unknown Object (MLST).
reames resigned from this revision.Oct 8 2015, 10:27 AM
reames removed a reviewer: reames.

Resigning as a reviewer to get a very stale review off my list of blocking tasks in phabricator. Please readd when desired.

hfinkel updated this revision to Diff 63351.Jul 8 2016, 4:07 PM

Rebased.

Herald added a subscriber: mcrosier. · View Herald TranscriptJul 8 2016, 4:07 PM
majnemer accepted this revision.Jul 10 2016, 1:09 AM
majnemer added a reviewer: majnemer.
majnemer added a subscriber: majnemer.

LGTM

lib/Analysis/Loads.cpp
104

const auto *

This revision is now accepted and ready to land.Jul 10 2016, 1:09 AM
Closed by commit rL275038: Teach isDereferenceablePointer to look through returned-argument functions (authored by hfinkel). · Explain WhyJul 10 2016, 8:16 PM
This revision was automatically updated to reflect the committed changes.
lebedev.ri added a subscriber: lebedev.ri.Dec 19 2018, 2:35 AM
Herald added a subscriber: bollu. · View Herald TranscriptDec 19 2018, 2:35 AM
lebedev.ri added a child revision: D9385: llvm.noalias - Look through noalias for shouldAlignPointerArgs.Dec 19 2018, 2:51 AM
lebedev.ri added a parent revision: D9383: returned - BasicAA should look through functions with returned arguments.

Revision Contents

PathSize
lib/
Analysis/
5 lines
test/
Analysis/
ValueTracking/
9 lines

Diff 63351

lib/Analysis/Loads.cpp

Show First 20 Lines • Show All 95 Lines • ▼ Show 20 Linesstatic bool isDereferenceableAndAlignedPointer(
if (const GCRelocateInst *RelocateInst = dyn_cast<GCRelocateInst>(V)) if (const GCRelocateInst *RelocateInst = dyn_cast<GCRelocateInst>(V))
return isDereferenceableAndAlignedPointer( return isDereferenceableAndAlignedPointer(
RelocateInst->getDerivedPtr(), Align, Size, DL, CtxI, DT, Visited); RelocateInst->getDerivedPtr(), Align, Size, DL, CtxI, DT, Visited);
if (const AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(V)) if (const AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(V))
return isDereferenceableAndAlignedPointer(ASC->getOperand(0), Align, Size, return isDereferenceableAndAlignedPointer(ASC->getOperand(0), Align, Size,
DL, CtxI, DT, Visited); DL, CtxI, DT, Visited);
if (const IntrinsicInst *I = dyn_cast<IntrinsicInst>(V))
majnemerUnsubmitted
Not Done
ReplyInline Actions

const auto *

majnemer: `const auto *`
if (I->getIntrinsicID() == Intrinsic::noalias)
return isDereferenceableAndAlignedPointer(I->getOperand(0), Align, Size,
DL, CtxI, DT, Visited);
// If we don't know, assume the worst. // If we don't know, assume the worst.
return false; return false;
} }
bool llvm::isDereferenceableAndAlignedPointer(const Value *V, unsigned Align, bool llvm::isDereferenceableAndAlignedPointer(const Value *V, unsigned Align,
const DataLayout &DL, const DataLayout &DL,
const Instruction *CtxI, const Instruction *CtxI,
const DominatorTree *DT) { const DominatorTree *DT) {
▲ Show 20 Lines • Show All 304 Lines • Show Last 20 Lines

test/Analysis/ValueTracking/memory-dereferenceable.ll

Show All 37 Lines; CHECK: %dparam{{.*}}(aligned)
%load3 = load i32, i32 addrspace(1)* %dparam %load3 = load i32, i32 addrspace(1)* %dparam
; CHECK: %relocate{{.*}}(aligned) ; CHECK: %relocate{{.*}}(aligned)
%tok = tail call token (i64, i32, i1 ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_i1f(i64 0, i32 0, i1 ()* @return_i1, i32 0, i32 0, i32 0, i32 0, i32 addrspace(1)* %dparam) %tok = tail call token (i64, i32, i1 ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_i1f(i64 0, i32 0, i1 ()* @return_i1, i32 0, i32 0, i32 0, i32 0, i32 addrspace(1)* %dparam)
%relocate = call i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(token %tok, i32 7, i32 7) %relocate = call i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(token %tok, i32 7, i32 7)
%load4 = load i32, i32 addrspace(1)* %relocate %load4 = load i32, i32 addrspace(1)* %relocate
; CHECK-NOT: %nparam ; CHECK-NOT: %nparam
%nparam = getelementptr i32, i32 addrspace(1)* %dparam, i32 5 %dpa = call i32 addrspace(1)* @llvm.noalias.p1i32(i32 addrspace(1)* %dparam, metadata !4)
%nparam = getelementptr i32, i32 addrspace(1)* %dpa, i32 5
%load5 = load i32, i32 addrspace(1)* %nparam %load5 = load i32, i32 addrspace(1)* %nparam
; Load from a non-dereferenceable load ; Load from a non-dereferenceable load
; CHECK-NOT: %nd_load ; CHECK-NOT: %nd_load
%nd_load = load i32*, i32** @globali32ptr %nd_load = load i32*, i32** @globali32ptr
%load6 = load i32, i32* %nd_load %load6 = load i32, i32* %nd_load
; Load from a dereferenceable load ; Load from a dereferenceable load
▲ Show 20 Lines • Show All 102 Lines • ▼ Show 20 Lines
if.end: if.end:
ret void ret void
} }
declare token @llvm.experimental.gc.statepoint.p0f_i1f(i64, i32, i1 ()*, i32, i32, ...) declare token @llvm.experimental.gc.statepoint.p0f_i1f(i64, i32, i1 ()*, i32, i32, ...)
declare i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(token, i32, i32) declare i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(token, i32, i32)
declare i32 addrspace(1)* @llvm.noalias.p1i32(i32 addrspace(1)*, metadata) nounwind argmemonly
!0 = !{i64 4} !0 = !{i64 4}
!1 = !{i64 2} !1 = !{i64 2}
!2 = !{} !2 = !{}
!3 = !{!3, !"some domain"}
!4 = !{!4, !3, !"some scope"}