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DanielKristofKissDanielKristofKiss
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[LLVM] Autoupgrade function attributes from Module attributes.
Refactoring #82763 to cache module attributes.
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+160
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‎lld/test/ELF/lto/aarch64_inline.ll‎

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@@ -0,0 +1,51 @@
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; REQUIRES: aarch64
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;; Test verifies inlining happens cross module when module flags are upgraded
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;; by the thin-lto linker/IRMover.
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;; Regression test for #82763
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; RUN: split-file %s %t
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; RUN: opt -thinlto-bc -thinlto-split-lto-unit -unified-lto %t/foo.s -o %t/foo.o
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; RUN: opt -thinlto-bc -thinlto-split-lto-unit -unified-lto %t/main.s -o %t/main.o
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; RUN: ld.lld -O2 --lto=thin --entry=main %t/main.o %t/foo.o -o %t/exe
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; RUN: llvm-objdump -d %t/exe | FileCheck %s
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; CHECK-LABEL: <main>:
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; CHECK-NEXT: pacibsp
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; CHECK-NEXT: mov w0, #0x22
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; CHECK-NEXT: autibsp
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; CHECK-NEXT: ret
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;--- foo.s
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target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
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target triple = "aarch64-unknown-linux-gnu"
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define dso_local noundef i32 @foo() local_unnamed_addr #0 {
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entry:
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ret i32 34
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}
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attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(none) }
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!llvm.module.flags = !{!0, !1, !2, !3 }
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!0 = !{i32 8, !"branch-target-enforcement", i32 1}
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!1 = !{i32 8, !"sign-return-address", i32 1}
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!2 = !{i32 8, !"sign-return-address-all", i32 1}
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!3 = !{i32 8, !"sign-return-address-with-bkey", i32 1}
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;--- main.s
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target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
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target triple = "aarch64-unknown-linux-gnu"
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declare i32 @foo();
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define i32 @main() {
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entry:
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%1 = call i32 @foo()
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ret i32 %1
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}
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!llvm.module.flags = !{!0, !1, !2, !3 }
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!0 = !{i32 8, !"branch-target-enforcement", i32 1}
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!1 = !{i32 8, !"sign-return-address", i32 1}
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!2 = !{i32 8, !"sign-return-address-all", i32 1}
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!3 = !{i32 8, !"sign-return-address-with-bkey", i32 1}

‎llvm/include/llvm/IR/AutoUpgrade.h‎

Lines changed: 3 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -88,6 +88,9 @@ namespace llvm {
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/// info. Return true if module is modified.
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bool UpgradeDebugInfo(Module &M);
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/// Copies module attributes to the functions in the module.
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void CopyModuleAttrToFunctions(Module &M);
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/// Check whether a string looks like an old loop attachment tag.
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inline bool mayBeOldLoopAttachmentTag(StringRef Name) {
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return Name.starts_with("llvm.vectorizer.");

‎llvm/lib/IR/AutoUpgrade.cpp‎

Lines changed: 47 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -5178,6 +5178,53 @@ void llvm::UpgradeFunctionAttributes(Function &F) {
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Arg.removeAttrs(AttributeFuncs::typeIncompatible(Arg.getType()));
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}
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// Check if the module attribute is present and not zero.
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static bool isModuleAttributeSet(Module &M, const StringRef &ModAttr) {
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const auto *Attr =
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mdconst::extract_or_null<ConstantInt>(M.getModuleFlag(ModAttr));
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return Attr && Attr->isOne();
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}
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// Check if the function attribute is not present and set it.
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static void SetFunctionAttrIfNotSet(Function &F, StringRef FnAttrName,
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StringRef Value) {
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if (!F.hasFnAttribute(FnAttrName))
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F.addFnAttr(FnAttrName, Value);
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}
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void llvm::CopyModuleAttrToFunctions(Module &M) {
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Triple T(M.getTargetTriple());
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if (!T.isThumb() && !T.isARM() && !T.isAArch64())
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return;
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StringRef SignTypeValue = "none";
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if (isModuleAttributeSet(M, "sign-return-address-all"))
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SignTypeValue = "all";
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else if (isModuleAttributeSet(M, "sign-return-address"))
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SignTypeValue = "non-leaf";
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StringRef BTEValue =
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isModuleAttributeSet(M, "branch-target-enforcement") ? "true" : "false";
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StringRef BPPLValue =
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isModuleAttributeSet(M, "branch-protection-pauth-lr") ? "true" : "false";
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StringRef GCSValue =
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isModuleAttributeSet(M, "guarded-control-stack") ? "true" : "false";
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StringRef SignKeyValue =
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isModuleAttributeSet(M, "sign-return-address-with-bkey") ? "b_key"
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: "a_key";
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for (Function &F : M.getFunctionList()) {
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if (F.isDeclaration())
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continue;
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SetFunctionAttrIfNotSet(F, "sign-return-address", SignTypeValue);
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SetFunctionAttrIfNotSet(F, "branch-target-enforcement", BTEValue);
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SetFunctionAttrIfNotSet(F, "branch-protection-pauth-lr", BPPLValue);
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SetFunctionAttrIfNotSet(F, "guarded-control-stack", GCSValue);
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SetFunctionAttrIfNotSet(F, "sign-return-address-key", SignKeyValue);
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}
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}
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static bool isOldLoopArgument(Metadata *MD) {
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auto *T = dyn_cast_or_null<MDTuple>(MD);
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if (!T)

‎llvm/lib/Linker/IRMover.cpp‎

Lines changed: 10 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1623,6 +1623,11 @@ Error IRLinker::run() {
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// Loop over all of the linked values to compute type mappings.
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computeTypeMapping();
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1626+
// Convert module level attributes to function level attributes because
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// after merging modules the attributes might change and would have different
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// effect on the functions as the original module would have.
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CopyModuleAttrToFunctions(*SrcM);
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16261631
std::reverse(Worklist.begin(), Worklist.end());
16271632
while (!Worklist.empty()) {
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GlobalValue *GV = Worklist.back();
@@ -1787,6 +1792,11 @@ IRMover::IRMover(Module &M) : Composite(M) {
17871792
for (const auto *MD : StructTypes.getVisitedMetadata()) {
17881793
SharedMDs[MD].reset(const_cast<MDNode *>(MD));
17891794
}
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// Convert module level attributes to function level attributes because
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// after merging modules the attributes might change and would have different
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// effect on the functions as the original module would have.
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CopyModuleAttrToFunctions(M);
17901800
}
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17921802
Error IRMover::move(std::unique_ptr<Module> Src,

‎llvm/test/LTO/AArch64/link-branch-target-enforcement.ll‎

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Original file line numberDiff line numberDiff line change
@@ -30,8 +30,11 @@ entry:
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; CHECK-NOT: linking module flags 'branch-target-enforcement': IDs have conflicting values in
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; CHECK-DUMP: <main>:
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; CHECK-DUMP: paciasp
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; CHECK-DUMP: str
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; CHECK-DUMP: bl 0x8 <main+0x8>
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; CHECK-DUMP: <foo>:
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; CHECK-DUMP: pacibsp
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3639
; `main` doesn't support BTI while `foo` does, so in the binary
3740
; we should see only PAC which is supported by both.

‎llvm/test/LTO/AArch64/link-sign-return-address.ll‎

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@@ -0,0 +1,43 @@
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; Testcase to check that module with different sign return address can
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; be mixed.
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;
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; RUN: llvm-as %s -o %t1.bc
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; RUN: llvm-as %p/Inputs/foo.ll -o %t2.bc
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; RUN: llvm-lto -exported-symbol main \
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; RUN: -exported-symbol foo \
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; RUN: -filetype=obj \
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; RUN: %t2.bc %t1.bc \
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; RUN: -o %t1.exe 2>&1
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; RUN: llvm-objdump -d %t1.exe | FileCheck --check-prefix=CHECK-DUMP %s
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; RUN: llvm-readelf -n %t1.exe | FileCheck --allow-empty --check-prefix=CHECK-PROP %s
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target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
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target triple = "aarch64-unknown-linux-gnu"
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declare i32 @foo();
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define i32 @main() {
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entry:
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%add = call i32 @foo()
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ret i32 %add
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}
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!llvm.module.flags = !{!0, !1, !2, !3 }
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!0 = !{i32 8, !"branch-target-enforcement", i32 0}
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!1 = !{i32 8, !"sign-return-address", i32 0}
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!2 = !{i32 8, !"sign-return-address-all", i32 0}
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!3 = !{i32 8, !"sign-return-address-with-bkey", i32 0}
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; CHECK-DUMP: <foo>:
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; CHECK-DUMP: pacibsp
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; CHECK-DUMP: mov w0, #0x2a
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; CHECK-DUMP: autibsp
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; CHECK-DUMP: ret
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; CHECK-DUMP: <main>:
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; CHECK-DUMP-NOT: paciasp
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; CHECK-DUMP: str x30,
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; CHECK-DUMP: bl 0x14 <main+0x4>
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; `main` doesn't support PAC sign-return-address while `foo` does, so in the binary
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; we should not see anything.
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; CHECK-PROP-NOT: Properties: aarch64 feature: PAC

‎llvm/test/Linker/link-arm-and-thumb.ll‎

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Original file line numberDiff line numberDiff line change
@@ -13,11 +13,11 @@ entry:
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ret i32 %add
1414
}
1515

16-
; CHECK: define i32 @main() {
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; CHECK: define i32 @main()
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; CHECK: define i32 @foo(i32 %a, i32 %b) [[ARM_ATTRS:#[0-9]+]]
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; CHECK: define i32 @bar(i32 %a, i32 %b) [[THUMB_ATTRS:#[0-9]+]]
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; CHECK: attributes [[ARM_ATTRS]] = { "target-features"="-thumb-mode" }
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; CHECK: attributes [[THUMB_ATTRS]] = { "target-features"="+thumb-mode" }
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; CHECK: attributes [[ARM_ATTRS]] = {{{.*}}"target-features"="-thumb-mode" }
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; CHECK: attributes [[THUMB_ATTRS]] = {{{.*}}"target-features"="+thumb-mode" }
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2323
; STDERR-NOT: warning: Linking two modules of different target triples:

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