[ThinLTO] Always import constants

This patch imports constant variables even when they can't be internalized
(which results in promotion). This offers some extra constant folding
opportunities.

Differential revision: https://reviews.llvm.org/D70404
This commit is contained in:
evgeny 2020-01-15 19:29:01 +03:00
parent 3f3017e162
commit 10cadee5ce
19 changed files with 187 additions and 35 deletions

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@ -757,14 +757,29 @@ private:
public:
struct GVarFlags {
GVarFlags(bool ReadOnly, bool WriteOnly)
: MaybeReadOnly(ReadOnly), MaybeWriteOnly(WriteOnly) {}
GVarFlags(bool ReadOnly, bool WriteOnly, bool Constant)
: MaybeReadOnly(ReadOnly), MaybeWriteOnly(WriteOnly),
Constant(Constant) {}
// In permodule summaries both MaybeReadOnly and MaybeWriteOnly
// bits are set, because attribute propagation occurs later on
// thin link phase.
// If true indicates that this global variable might be accessed
// purely by non-volatile load instructions. This in turn means
// it can be internalized in source and destination modules during
// thin LTO import because it neither modified nor its address
// is taken.
unsigned MaybeReadOnly : 1;
// If true indicates that variable is possibly only written to, so
// its value isn't loaded and its address isn't taken anywhere.
// False, when 'Constant' attribute is set.
unsigned MaybeWriteOnly : 1;
// Indicates that value is a compile-time constant. Global variable
// can be 'Constant' while not being 'ReadOnly' on several occasions:
// - it is volatile, (e.g mapped device address)
// - its address is taken, meaning that unlike 'ReadOnly' vars we can't
// internalize it.
// Constant variables are always imported thus giving compiler an
// opportunity to make some extra optimizations. Readonly constants
// are also internalized.
unsigned Constant : 1;
} VarFlags;
GlobalVarSummary(GVFlags Flags, GVarFlags VarFlags,
@ -782,6 +797,7 @@ public:
void setWriteOnly(bool WO) { VarFlags.MaybeWriteOnly = WO; }
bool maybeReadOnly() const { return VarFlags.MaybeReadOnly; }
bool maybeWriteOnly() const { return VarFlags.MaybeWriteOnly; }
bool isConstant() const { return VarFlags.Constant; }
void setVTableFuncs(VTableFuncList Funcs) {
assert(!VTableFuncs);

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@ -599,7 +599,9 @@ static void computeVariableSummary(ModuleSummaryIndex &Index,
bool CanBeInternalized =
!V.hasComdat() && !V.hasAppendingLinkage() && !V.isInterposable() &&
!V.hasAvailableExternallyLinkage() && !V.hasDLLExportStorageClass();
GlobalVarSummary::GVarFlags VarFlags(CanBeInternalized, CanBeInternalized);
bool Constant = V.isConstant();
GlobalVarSummary::GVarFlags VarFlags(
CanBeInternalized, Constant ? false : CanBeInternalized, Constant);
auto GVarSummary = std::make_unique<GlobalVarSummary>(Flags, VarFlags,
RefEdges.takeVector());
if (NonRenamableLocal)
@ -718,7 +720,9 @@ ModuleSummaryIndex llvm::buildModuleSummaryIndex(
} else {
std::unique_ptr<GlobalVarSummary> Summary =
std::make_unique<GlobalVarSummary>(
GVFlags, GlobalVarSummary::GVarFlags(false, false),
GVFlags,
GlobalVarSummary::GVarFlags(
false, false, cast<GlobalVariable>(GV)->isConstant()),
ArrayRef<ValueInfo>{});
Index.addGlobalValueSummary(*GV, std::move(Summary));
}

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@ -8155,7 +8155,8 @@ bool LLParser::ParseVariableSummary(std::string Name, GlobalValue::GUID GUID,
/*Linkage=*/GlobalValue::ExternalLinkage, /*NotEligibleToImport=*/false,
/*Live=*/false, /*IsLocal=*/false, /*CanAutoHide=*/false);
GlobalVarSummary::GVarFlags GVarFlags(/*ReadOnly*/ false,
/* WriteOnly */ false);
/* WriteOnly */ false,
/* Constant */ false);
std::vector<ValueInfo> Refs;
VTableFuncList VTableFuncs;
if (ParseToken(lltok::colon, "expected ':' here") ||
@ -8827,7 +8828,8 @@ bool LLParser::ParseGVFlags(GlobalValueSummary::GVFlags &GVFlags) {
/// GVarFlags
/// ::= 'varFlags' ':' '(' 'readonly' ':' Flag
/// ',' 'writeonly' ':' Flag ')'
/// ',' 'writeonly' ':' Flag
/// ',' 'constant' ':' Flag ')'
bool LLParser::ParseGVarFlags(GlobalVarSummary::GVarFlags &GVarFlags) {
assert(Lex.getKind() == lltok::kw_varFlags);
Lex.Lex();
@ -8856,6 +8858,11 @@ bool LLParser::ParseGVarFlags(GlobalVarSummary::GVarFlags &GVarFlags) {
return true;
GVarFlags.MaybeWriteOnly = Flag;
break;
case lltok::kw_constant:
if (ParseRest(Flag))
return true;
GVarFlags.Constant = Flag;
break;
default:
return Error(Lex.getLoc(), "expected gvar flag type");
}

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@ -986,7 +986,8 @@ static GlobalValueSummary::GVFlags getDecodedGVSummaryFlags(uint64_t RawFlags,
// Decode the flags for GlobalVariable in the summary
static GlobalVarSummary::GVarFlags getDecodedGVarFlags(uint64_t RawFlags) {
return GlobalVarSummary::GVarFlags((RawFlags & 0x1) ? true : false,
(RawFlags & 0x2) ? true : false);
(RawFlags & 0x2) ? true : false,
(RawFlags & 0x4) ? true : false);
}
static GlobalValue::VisibilityTypes getDecodedVisibility(unsigned Val) {
@ -5965,7 +5966,8 @@ Error ModuleSummaryIndexBitcodeReader::parseEntireSummary(unsigned ID) {
uint64_t RawFlags = Record[1];
unsigned RefArrayStart = 2;
GlobalVarSummary::GVarFlags GVF(/* ReadOnly */ false,
/* WriteOnly */ false);
/* WriteOnly */ false,
/* Constant */ false);
auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
if (Version >= 5) {
GVF = getDecodedGVarFlags(Record[2]);
@ -6101,7 +6103,8 @@ Error ModuleSummaryIndexBitcodeReader::parseEntireSummary(unsigned ID) {
uint64_t RawFlags = Record[2];
unsigned RefArrayStart = 3;
GlobalVarSummary::GVarFlags GVF(/* ReadOnly */ false,
/* WriteOnly */ false);
/* WriteOnly */ false,
/* Constant */ false);
auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
if (Version >= 5) {
GVF = getDecodedGVarFlags(Record[3]);

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@ -1028,7 +1028,8 @@ static uint64_t getEncodedGVSummaryFlags(GlobalValueSummary::GVFlags Flags) {
}
static uint64_t getEncodedGVarFlags(GlobalVarSummary::GVarFlags Flags) {
uint64_t RawFlags = Flags.MaybeReadOnly | (Flags.MaybeWriteOnly << 1);
uint64_t RawFlags =
Flags.MaybeReadOnly | (Flags.MaybeWriteOnly << 1) | (Flags.Constant << 2);
return RawFlags;
}

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@ -2901,7 +2901,8 @@ void AssemblyWriter::printAliasSummary(const AliasSummary *AS) {
void AssemblyWriter::printGlobalVarSummary(const GlobalVarSummary *GS) {
Out << ", varFlags: (readonly: " << GS->VarFlags.MaybeReadOnly << ", "
<< "writeonly: " << GS->VarFlags.MaybeWriteOnly << ")";
<< "writeonly: " << GS->VarFlags.MaybeWriteOnly << ", "
<< "constant: " << GS->VarFlags.Constant << ")";
auto VTableFuncs = GS->vTableFuncs();
if (!VTableFuncs.empty()) {

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@ -221,7 +221,8 @@ bool ModuleSummaryIndex::canImportGlobalVar(GlobalValueSummary *S,
// c) Link error (external declaration with internal definition).
// However we do not promote objects referenced by writeonly GV
// initializer by means of converting it to 'zeroinitializer'
return !isReadOnly(GVS) && !isWriteOnly(GVS) && GVS->refs().size();
return !GVS->isConstant() && !isReadOnly(GVS) && !isWriteOnly(GVS) &&
GVS->refs().size();
};
auto *GVS = cast<GlobalVarSummary>(S->getBaseObject());
@ -405,6 +406,12 @@ static bool hasWriteOnlyFlag(const GlobalValueSummary *S) {
return false;
}
static bool hasConstantFlag(const GlobalValueSummary *S) {
if (auto *GVS = dyn_cast<GlobalVarSummary>(S))
return GVS->isConstant();
return false;
}
void ModuleSummaryIndex::exportToDot(
raw_ostream &OS,
const DenseSet<GlobalValue::GUID> &GUIDPreservedSymbols) const {
@ -482,6 +489,8 @@ void ModuleSummaryIndex::exportToDot(
A.addComment("immutable");
if (Flags.Live && hasWriteOnlyFlag(SummaryIt.second))
A.addComment("writeOnly");
if (Flags.Live && hasConstantFlag(SummaryIt.second))
A.addComment("constant");
}
if (Flags.DSOLocal)
A.addComment("dsoLocal");

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@ -76,10 +76,10 @@
; CHECK: ^8 = gv: (guid: 7, summaries: (function: (module: ^0, flags: (linkage: linkonce_odr, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 1)))
; CHECK: ^9 = gv: (guid: 8, summaries: (function: (module: ^0, flags: (linkage: weak_odr, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 1), insts: 1)))
; CHECK: ^10 = gv: (guid: 9, summaries: (function: (module: ^0, flags: (linkage: weak, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 1)))
; CHECK: ^11 = gv: (guid: 10, summaries: (variable: (module: ^0, flags: (linkage: common, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0))))
; CHECK: ^12 = gv: (guid: 11, summaries: (variable: (module: ^0, flags: (linkage: appending, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0), refs: (^4))))
; CHECK: ^13 = gv: (guid: 12, summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 0))))
; CHECK: ^14 = gv: (guid: 13, summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0))))
; CHECK: ^11 = gv: (guid: 10, summaries: (variable: (module: ^0, flags: (linkage: common, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0, constant: 0))))
; CHECK: ^12 = gv: (guid: 11, summaries: (variable: (module: ^0, flags: (linkage: appending, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0, constant: 0), refs: (^4))))
; CHECK: ^13 = gv: (guid: 12, summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 0, constant: 0))))
; CHECK: ^14 = gv: (guid: 13, summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0, constant: 0))))
; CHECK: ^15 = gv: (guid: 14, summaries: (function: (module: ^1, flags: (linkage: external, notEligibleToImport: 1, live: 1, dsoLocal: 0, canAutoHide: 0), insts: 1, funcFlags: (readNone: 0, readOnly: 0, noRecurse: 0, returnDoesNotAlias: 0, noInline: 1, alwaysInline: 0))))
; CHECK: ^16 = gv: (guid: 15, summaries: (function: (module: ^1, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 1, funcFlags: (readNone: 1, readOnly: 0, noRecurse: 1, returnDoesNotAlias: 0, noInline: 0, alwaysInline: 1))))
; CHECK: ^17 = gv: (guid: 16, summaries: (function: (module: ^1, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 1, funcFlags: (readNone: 0, readOnly: 1, noRecurse: 0, returnDoesNotAlias: 1, noInline: 0, alwaysInline: 0), calls: ((callee: ^15)))))

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@ -29,9 +29,9 @@ declare i32 @_ZN1C1fEi(%struct.C*, i32)
^0 = module: (path: "<stdin>", hash: (0, 0, 0, 0, 0))
^1 = gv: (name: "_ZN1A1nEi") ; guid = 1621563287929432257
^2 = gv: (name: "_ZTV1B", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0), vTableFuncs: ((virtFunc: ^3, offset: 16), (virtFunc: ^1, offset: 24)), refs: (^3, ^1)))) ; guid = 5283576821522790367
^2 = gv: (name: "_ZTV1B", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0, constant: 0), vTableFuncs: ((virtFunc: ^3, offset: 16), (virtFunc: ^1, offset: 24)), refs: (^3, ^1)))) ; guid = 5283576821522790367
^3 = gv: (name: "_ZN1B1fEi") ; guid = 7162046368816414394
^4 = gv: (name: "_ZTV1C", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0), vTableFuncs: ((virtFunc: ^5, offset: 16), (virtFunc: ^1, offset: 24)), refs: (^1, ^5)))) ; guid = 13624023785555846296
^4 = gv: (name: "_ZTV1C", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 0, writeonly: 0, constant: 0), vTableFuncs: ((virtFunc: ^5, offset: 16), (virtFunc: ^1, offset: 24)), refs: (^1, ^5)))) ; guid = 13624023785555846296
^5 = gv: (name: "_ZN1C1fEi") ; guid = 14876272565662207556
^6 = typeidCompatibleVTable: (name: "_ZTS1A", summary: ((offset: 16, ^2), (offset: 16, ^4))) ; guid = 7004155349499253778
^7 = typeidCompatibleVTable: (name: "_ZTS1B", summary: ((offset: 16, ^2))) ; guid = 6203814149063363976

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@ -73,7 +73,7 @@ target triple = "x86_64-unknown-linux-gnu"
@bar = global void (...)* bitcast (void ()* @func to void (...)*), align 8
@globalvar = global i32 0, align 4
@globalvar = constant i32 0, align 4
declare void @func() #0
declare i32 @func2(...) #1
@ -154,11 +154,12 @@ entry:
; DIS-DAG: = gv: (name: "foo") ; guid = 6699318081062747564
; DIS-DAG: = gv: (name: "func") ; guid = 7289175272376759421
; DIS-DAG: = gv: (name: "func3") ; guid = 11517462787082255043
; DIS-DAG: = gv: (name: "globalvar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 1)))) ; guid = 12887606300320728018
; Check that default value of writeonly attribute is zero for constant variables
; DIS-DAG: = gv: (name: "globalvar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 0, constant: 1)))) ; guid = 12887606300320728018
; DIS-DAG: = gv: (name: "func2") ; guid = 14069196320850861797
; DIS-DAG: = gv: (name: "llvm.ctpop.i8") ; guid = 15254915475081819833
; DIS-DAG: = gv: (name: "main", summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 9, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 15822663052811949562
; DIS-DAG: = gv: (name: "bar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 1), refs: (^{{.*}})))) ; guid = 16434608426314478903
; DIS-DAG: = gv: (name: "bar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 1, constant: 0), refs: (^{{.*}})))) ; guid = 16434608426314478903
; Don't try to match the exact GUID. Since it is private, the file path
; will get hashed, and that will be test dependent.
; DIS-DAG: = gv: (name: "Y", summaries: (function: (module: ^0, flags: (linkage: private, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), insts: 14, calls: ((callee: ^{{.*}}))))) ; guid =

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@ -2,7 +2,7 @@ target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16
target triple = "x86_64-unknown-linux-gnu"
@A = local_unnamed_addr global i32 10, align 4
@B = local_unnamed_addr global i32 20, align 4
@B = local_unnamed_addr constant i32 20, align 4
; Function Attrs: norecurse nounwind readonly uwtable
define i32 @foo() local_unnamed_addr #0 {

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@ -0,0 +1,15 @@
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
%struct.S = type { i32, i32, i32* }
%struct.Q = type { %struct.S* }
@val = dso_local global i32 42, align 4
@_ZL3Obj = internal constant %struct.S { i32 4, i32 8, i32* @val }, align 8
@outer = dso_local local_unnamed_addr global %struct.Q { %struct.S* @_ZL3Obj }, align 8
define dso_local nonnull %struct.S* @_Z6getObjv() local_unnamed_addr {
entry:
store %struct.S* null, %struct.S** getelementptr inbounds (%struct.Q, %struct.Q* @outer, i64 0, i32 0), align 8
ret %struct.S* @_ZL3Obj
}

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@ -0,0 +1,10 @@
source_filename = "bar.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@foo = external dso_local local_unnamed_addr constant i32, align 4
define dso_local i32 @_Z3barv() local_unnamed_addr {
entry:
%0 = load i32, i32* @foo, align 4
ret i32 %0
}

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@ -0,0 +1,5 @@
source_filename = "foo.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@foo = dso_local local_unnamed_addr constant i32 21, align 4

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@ -52,7 +52,7 @@
; COMBINED-NEXT: node [style=filled,fillcolor=lightblue];
; COMBINED-NEXT: M1_[[FOO:[0-9]+]] [shape="record",label="foo|extern (inst: 4, ffl: 000010)}"]; // function
; COMBINED-NEXT: M1_[[A:[0-9]+]] [shape="Mrecord",label="A|extern}"]; // variable, immutable
; COMBINED-NEXT: M1_[[B:[0-9]+]] [shape="Mrecord",label="B|extern}"]; // variable, immutable
; COMBINED-NEXT: M1_[[B:[0-9]+]] [shape="Mrecord",label="B|extern}"]; // variable, immutable, constant
; COMBINED-NEXT: M1_{{[0-9]+}} [shape="record",label="bar|extern (inst: 1, ffl: 000000)}",fillcolor="red"]; // function, dead
; COMBINED-NEXT: // Edges:
; COMBINED-NEXT: M1_[[FOO]] -> M1_[[B]] [style=dashed,color=forestgreen]; // const-ref

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@ -0,0 +1,47 @@
; Check that we promote constant object in the source module and import it
; even when it is referenced in some other GV initializer and/or is used
; by store instructions.
; RUN: opt -thinlto-bc %s -o %t1.bc
; RUN: opt -thinlto-bc %p/Inputs/import-constant.ll -o %t2.bc
; RUN: llvm-lto2 run -save-temps %t1.bc %t2.bc -o %t-out \
; RUN: -r=%t1.bc,main,plx \
; RUN: -r=%t1.bc,_Z6getObjv,l \
; RUN: -r=%t2.bc,_Z6getObjv,pl \
; RUN: -r=%t2.bc,val,pl \
; RUN: -r=%t2.bc,outer,pl
; RUN: llvm-dis %t-out.2.1.promote.bc -o - | FileCheck %s --check-prefix=PROMOTE
; RUN: llvm-dis %t-out.1.3.import.bc -o - | FileCheck %s --check-prefix=IMPORT
; RUN: llvm-dis %t-out.1.4.opt.bc -o - | FileCheck %s --check-prefix=OPT
; Check that variable has been promoted in the source module
; PROMOTE: @_ZL3Obj.llvm.{{.*}} = hidden constant %struct.S { i32 4, i32 8, i32* @val }
; @outer is a write-only variable, so it's been converted to zeroinitializer.
; IMPORT: @outer = internal local_unnamed_addr global %struct.Q zeroinitializer
; IMPORT-NEXT: @_ZL3Obj.llvm.{{.*}} = available_externally hidden constant %struct.S { i32 4, i32 8, i32* @val }
; IMPORT-NEXT: @val = external dso_local global i32
; OPT: @outer = internal unnamed_addr global %struct.Q zeroinitializer
; OPT: define dso_local i32 @main()
; OPT-NEXT: entry:
; OPT-NEXT: store %struct.S* null, %struct.S** getelementptr inbounds (%struct.Q, %struct.Q* @outer, i64 0, i32 0)
; OPT-NEXT: ret i32 12
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
%struct.S = type { i32, i32, i32* }
define dso_local i32 @main() local_unnamed_addr {
entry:
%call = tail call %struct.S* @_Z6getObjv()
%d = getelementptr inbounds %struct.S, %struct.S* %call, i64 0, i32 0
%0 = load i32, i32* %d, align 8
%v = getelementptr inbounds %struct.S, %struct.S* %call, i64 0, i32 1
%1 = load i32, i32* %v, align 4
%add = add nsw i32 %1, %0
ret i32 %add
}
declare dso_local %struct.S* @_Z6getObjv() local_unnamed_addr

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@ -0,0 +1,34 @@
; Check that we internalize external constant if it is accessed
; purely by non-volatile loads.
; RUN: opt -thinlto-bc %s -o %t-main
; RUN: opt -thinlto-bc %p/Inputs/import-ro-constant-foo.ll -o %t-foo
; RUN: opt -thinlto-bc %p/Inputs/import-ro-constant-bar.ll -o %t-bar
; RUN: llvm-lto2 run -save-temps -o %t-out %t-main %t-foo %t-bar \
; RUN: -r=%t-foo,foo,pl \
; RUN: -r=%t-main,main,plx \
; RUN: -r=%t-main,_Z3barv,l \
; RUN: -r=%t-main,foo, \
; RUN: -r=%t-bar,_Z3barv,pl \
; RUN: -r=%t-bar,foo,
; RUN: llvm-dis %t-out.1.3.import.bc -o - | FileCheck %s --check-prefix=IMPORT
; RUN: llvm-dis %t-out.1.4.opt.bc -o - | FileCheck %s --check-prefix=OPT
; IMPORT: @foo = internal local_unnamed_addr constant i32 21, align 4 #0
; IMPORT: attributes #0 = { "thinlto-internalize" }
; OPT: i32 @main()
; OPT-NEXT: entry:
; OPT-NEXT: ret i32 42
source_filename = "main.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@foo = external dso_local local_unnamed_addr constant i32, align 4
define dso_local i32 @main() local_unnamed_addr {
entry:
%0 = load i32, i32* @foo, align 4
%call = tail call i32 @_Z3barv()
%add = add nsw i32 %call, %0
ret i32 %add
}
declare dso_local i32 @_Z3barv() local_unnamed_addr

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@ -22,5 +22,5 @@ entry:
}
; CHECK: ^0 = module:
; CHECK-NEXT: ^1 = gv: (name: "obj", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 1)))) ; guid =
; CHECK-NEXT: ^1 = gv: (name: "obj", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), varFlags: (readonly: 1, writeonly: 1, constant: 0)))) ; guid =
; CHECK-NEXT: ^2 = gv: (name: "foo", summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), insts: 3, refs: (^1)))) ; guid =

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@ -3,14 +3,13 @@
; RUN: opt -module-summary %p/Inputs/referenced_by_constant.ll -o %t2.bc
; RUN: llvm-lto -thinlto-action=thinlink -o %t3.bc %t.bc %t2.bc
; Check the import side: we currently only import bar() (with a future
; enhancement to identify constants in the summary, we should mark
; @someglobal/@someglobal2 for import as a local copy, which would
; cause @referencedbyglobal and @localreferencedbyglobal to be exported
; and promoted).
; Check the import side: we currently import bar() and also promote/import
; referenced constant objects. There is stll a room for improvement: we
; can make a local copy of someglobal and someglobal2 because they are both
; 'unnamed_addr' constants. This should eventually be done as well.
; RUN: llvm-lto -thinlto-action=import %t.bc -thinlto-index=%t3.bc -o - | llvm-dis -o - | FileCheck %s --check-prefix=IMPORT
; IMPORT: @someglobal.llvm.0 = external hidden unnamed_addr constant
; IMPORT: @someglobal2.llvm.0 = external hidden unnamed_addr constant
; IMPORT: @someglobal.llvm.0 = available_externally hidden unnamed_addr constant i8* bitcast (void ()* @referencedbyglobal to i8*)
; IMPORT: @someglobal2.llvm.0 = available_externally hidden unnamed_addr constant i8* bitcast (void ()* @localreferencedbyglobal.llvm.0 to i8*)
; IMPORT: define available_externally void @bar()
; Check the export side: we currently only export bar(), which causes
@ -19,7 +18,7 @@
; EXPORT: @someglobal.llvm.0 = hidden unnamed_addr constant
; EXPORT: @someglobal2.llvm.0 = hidden unnamed_addr constant
; EXPORT: define void @referencedbyglobal()
; EXPORT: define internal void @localreferencedbyglobal()
; EXPORT: define hidden void @localreferencedbyglobal.llvm
target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.11.0"