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Differential D153855

[StructuralHash] Ignore global variable declarations
ClosedPublic

Authored by uabelho on Jun 27 2023, 3:55 AM.

Details

Reviewers
aeubanks
nikic
Commits
rGd2640f596c47: [StructuralHash] Ignore global variable declarations
Summary

Ignore declarations of global variables, just as we do with declarations
of functions.

Done as a follow up to the comments in https://reviews.llvm.org/D149209.

Diff Detail

Event Timeline

uabelho created this revision.Jun 27 2023, 3:55 AM
Herald added a project: Restricted Project. · View Herald TranscriptJun 27 2023, 3:55 AM
Herald added subscribers: StephenFan, bjope, hiraditya. · View Herald Transcript
uabelho requested review of this revision.Jun 27 2023, 3:55 AM
Herald added a project: Restricted Project. · View Herald TranscriptJun 27 2023, 3:55 AM
Herald added a subscriber: llvm-commits. · View Herald Transcript
uabelho mentioned this in D149209: [StructuralHash] Track global variables.Jun 27 2023, 3:57 AM
Harbormaster completed remote builds in B241427: Diff 534902.Jun 27 2023, 4:28 AM
aeubanks added inline comments.Jun 27 2023, 9:11 AM
llvm/test/Transforms/StripDeadPrototypes/remove-global-variable-declaration.ll
9

all you need is this global declaration in the test, nothing else below is necessary

uabelho updated this revision to Diff 535236.Jun 27 2023, 10:26 PM

Simplified testcase

uabelho marked an inline comment as done.Jun 27 2023, 10:27 PM
uabelho added inline comments.
llvm/test/Transforms/StripDeadPrototypes/remove-global-variable-declaration.ll
9

Thanks!

Harbormaster completed remote builds in B241685: Diff 535236.Jun 27 2023, 11:13 PM
aeubanks accepted this revision.Jun 28 2023, 8:22 AM

lg

This revision is now accepted and ready to land.Jun 28 2023, 8:22 AM
aeubanks mentioned this in D146776: Reland [llvm] Preliminary fat-lto-objects support.Jun 28 2023, 11:15 AM
paulkirth mentioned this in D154019: [IR] Ignore globals with the `llvm.` prefix when calculating module hash.Jun 28 2023, 5:01 PM
Closed by commit rGd2640f596c47: [StructuralHash] Ignore global variable declarations (authored by uabelho). · Explain WhyJun 28 2023, 10:53 PM
This revision was automatically updated to reflect the committed changes.
uabelho marked an inline comment as done.
uabelho added a commit: rGd2640f596c47: [StructuralHash] Ignore global variable declarations.
paulkirth mentioned this in rGe8e499f5f9c4: [IR] Ignore globals with the `llvm.` prefix when calculating module hash.Jul 12 2023, 8:40 AM

Revision Contents

PathSize
llvm/
lib/
IR/
5 lines
test/
Transforms/
StripDeadPrototypes/
38 lines

Diff 534902

llvm/lib/IR/StructuralHash.cpp

Show First 20 Lines • Show All 52 Lines • ▼ Show 20 Lines while (!BBs.empty()) {
if (!VisitedBBs.insert(Term->getSuccessor(i)).second) if (!VisitedBBs.insert(Term->getSuccessor(i)).second)
continue; continue;
BBs.push_back(Term->getSuccessor(i)); BBs.push_back(Term->getSuccessor(i));
} }
} }
} }
void update(const GlobalVariable &GV) { void update(const GlobalVariable &GV) {
// used/compiler.used don't affect analyses. // Declarations and used/compiler.used don't affect analyses.
if (GV.getName() == "llvm.compiler.used" || GV.getName() == "llvm.used") if (GV.isDeclaration() || GV.getName() == "llvm.compiler.used" ||
GV.getName() == "llvm.used")
return; return;
hash(23456); // Global header hash(23456); // Global header
hash(GV.getValueType()->getTypeID()); hash(GV.getValueType()->getTypeID());
} }
void update(const Module &M) { void update(const Module &M) {
for (const GlobalVariable &GV : M.globals()) for (const GlobalVariable &GV : M.globals())
update(GV); update(GV);
Show All 20 Lines

llvm/test/Transforms/StripDeadPrototypes/remove-global-variable-declaration.ll

  • This file was added.
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
; RUN: opt -passes=strip-dead-prototypes -S -verify-analysis-invalidation < %s | FileCheck %s
; The declaration of the unused global variable @.str should be removed without
; getting any error from -verify-analysis-invalidation.
; CHECK-NOT: @.str
@.str = external constant [15 x i16]
aeubanksUnsubmitted
Done
ReplyInline Actions

all you need is this global declaration in the test, nothing else below is necessary

aeubanks: all you need is this global declaration in the test, nothing else below is necessary
uabelhoAuthorUnsubmitted
Done
ReplyInline Actions

Thanks!

uabelho: Thanks!
define i16 @_Z7test_itv() {
; CHECK-LABEL: define i16 @_Z7test_itv() {
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 0, ptr null)
; CHECK-NEXT: call void @llvm.dbg.declare(metadata ptr null, metadata [[META3:![0-9]+]], metadata !DIExpression()), !dbg [[DBG5:![0-9]+]]
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 0, ptr null)
; CHECK-NEXT: ret i16 0
;
entry:
call void @llvm.lifetime.start.p0(i64 0, ptr null)
call void @llvm.dbg.declare(metadata ptr null, metadata !3, metadata !DIExpression()), !dbg !5
call void @llvm.lifetime.end.p0(i64 0, ptr null)
ret i16 0
}
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture)
declare void @llvm.dbg.declare(metadata, metadata, metadata)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture)
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!2}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1)
!1 = !DIFile(filename: "t.C", directory: "/")
!2 = !{i32 2, !"Debug Info Version", i32 3}
!3 = !DILocalVariable(scope: !4)
!4 = distinct !DISubprogram(unit: !0)
!5 = !DILocation(scope: !4)