llvm-project/llvm/test/ThinLTO/X86/index-const-prop-linkage.ll
Fangrui Song 252a1eecc0 [ThinLTO] Respect ClearDSOLocalOnDeclarations for unimported functions
D74751 added `ClearDSOLocalOnDeclarations` and dropped dso_local for
isDeclarationForLinker `GlobalValue`s. It missed a case for imported
declarations (`doImportAsDefinition` is false while `isPerformingImport` is
true). This can lead to a linker error for a default visibility symbol in
`ld.lld -shared`.

When `ClearDSOLocalOnDeclarations` is true, we check
`isPerformingImport() && !doImportAsDefinition(&GV)` along with
`GV.isDeclarationForLinker()`. The new condition checks an imported declaration.

This patch fixes a `LLVMPolly.so` link error using a trunk clang -DLLVM_ENABLE_LTO=Thin.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D104986
2021-07-02 17:08:25 -07:00

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1.0 KiB
LLVM

; RUN: opt -module-summary %s -o %t1.bc
; RUN: opt -module-summary %p/Inputs/index-const-prop-linkage.ll -o %t2.bc
; RUN: llvm-lto2 run -save-temps %t2.bc -r=%t2.bc,foo,pl -r=%t2.bc,g1,pl -r=%t2.bc,g2,pl -r=%t2.bc,g3, \
; RUN: %t1.bc -r=%t1.bc,foo, -r=%t1.bc,main,plx -r=%t1.bc,g2, -o %t3
; RUN: llvm-dis %t3.2.3.import.bc -o - | FileCheck %s
; Check that we never internalize anything with:
; - appending linkage
; - common linkage
; - available_externally linkage
; - reference from @llvm.used
; CHECK: @llvm.used = appending global [1 x i32*] [i32* @g2]
; CHECK-NEXT: @g1 = external global i32, align 4
; CHECK-NEXT: @g2 = available_externally global i32 42, align 4
; CHECK-NEXT: @g3 = available_externally global i32 42, align 4
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"
declare i32 @foo()
@g2 = external global i32
@llvm.used = appending global [1 x i32*] [i32* @g2]
define i32 @main() {
%v = call i32 @foo()
ret i32 %v
}