llvm-mirror/test/ThinLTO/X86/local_name_conflict.ll
Teresa Johnson b934cad3f0 [ThinLTO] Import static functions from the same module as caller
Summary:
We can sometimes end up with multiple copies of a local function that
have the same GUID in the index. This happens when there are local
functions with the same name that are in different source files with the
same name (but in different directories), and they were compiled in
their own directory so had the same path at compile time.

In this case make sure we import the copy in the caller's module. While
it isn't a correctness problem (the renamed reference which is based on the
module IR hash will be unique since the module must have had an
externally visible function that was imported), importing the wrong copy
will result in lost performance opportunity since it won't be referenced
and inlined.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28440

llvm-svn: 291841
2017-01-12 22:04:45 +00:00

41 lines
1.8 KiB
LLVM

; Test handling when two files with the same source file name contain
; static functions with the same name (which will have the same GUID
; in the combined index.
; Do setup work for all below tests: generate bitcode and combined index
; RUN: opt -module-summary -module-hash %s -o %t.bc
; RUN: opt -module-summary -module-hash %p/Inputs/local_name_conflict1.ll -o %t2.bc
; RUN: opt -module-summary -module-hash %p/Inputs/local_name_conflict2.ll -o %t3.bc
; RUN: llvm-lto -thinlto-action=thinlink -o %t4.bc %t.bc %t2.bc %t3.bc
; This module will import b() which should cause the copy of foo from
; that module (%t3.bc) to be imported. Check that the imported reference's
; promoted name matches the imported copy.
; RUN: llvm-lto -thinlto-action=import %t.bc -thinlto-index=%t4.bc -o - | llvm-dis -o - | FileCheck %s --check-prefix=IMPORT
; IMPORT: call i32 @foo.llvm.[[HASH:[0-9A-F]+]]
; IMPORT: define available_externally hidden i32 @foo.llvm.[[HASH]]()
; The copy in %t2.bc should not be exported/promoted/renamed
; RUN: llvm-lto -thinlto-action=promote %t2.bc -thinlto-index=%t4.bc -o - | llvm-dis -o - | FileCheck %s --check-prefix=NOEXPORTSTATIC
; NOEXPORTSTATIC: define internal i32 @foo()
; Make sure foo is promoted and renamed without complaint in %t3.bc.
; RUN: llvm-lto -thinlto-action=promote %t3.bc -thinlto-index=%t4.bc -o - | llvm-dis -o - | FileCheck %s --check-prefix=EXPORTSTATIC
; EXPORTSTATIC: define hidden i32 @foo.llvm.
; ModuleID = 'local_name_conflict_main.o'
source_filename = "local_name_conflict_main.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Function Attrs: noinline nounwind uwtable
define i32 @main() {
entry:
%retval = alloca i32, align 4
store i32 0, i32* %retval, align 4
%call = call i32 (...) @b()
ret i32 %call
}
declare i32 @b(...)