cross-project-tests/dtlto/cache-extraction.test

REQUIRES: ld.lld

# Show that DTLTO input file extraction interacts correctly with the
# ThinLTO cache.
#
# To handle bitcode inputs that are not in individual files on disk, such as
# members of non-thin archives, DTLTO extracts such input bitcode to a
# temporary individual file on disk. This extraction should only be
# performed if the backend compilation is required. A backend compilation is
# only required if there is a miss in the ThinLTO cache for that module, or a
# module is imported by a module that has missed in the ThinLTO cache.
#
# Test DTLTO input extraction across three cases:
#   1. None of the backend compilations hit in the ThinLTO cache.
#   2. All of the backend compilations hit in the ThinLTO cache.
#   3. Some backend compilations hit in the ThinLTO cache and some miss.

RUN: rm -rf %t && split-file %s %t && cd %t

RUN: %clang --target=x86_64-linux-gnu -O2 -flto=thin -c f1.c f2.c
RUN: llvm-ar rcs f1.a f1.o
RUN: llvm-ar rcs f2.a f2.o

RUN: mkdir cache.dir

DEFINE: %{link} =  \
DEFINE:    %clang --target=x86_64-linux-gnu -fuse-ld=lld -shared -nostdlib \
DEFINE:     -O2 -flto=thin \
DEFINE:     -fthinlto-distributor=%python \
DEFINE:     -Xthinlto-distributor=%llvm_src_root/utils/dtlto/local.py \
DEFINE:     -Wl,--thinlto-cache-dir=cache.dir \
DEFINE:     -Wl,--save-temps

# 1. None of the backend compilations hit in the ThinLTO cache.
#
# Both f1.o and f2.o require backend compilation, so both should be extracted.
# Each backend compilation should produce:
#   * a thinlto.bc file
#   * a temporary bitcode file (extracted archive member)
# Native objects are moved into the ThinLTO cache and should not remain here.
RUN: mkdir none
RUN: %{link} -Wl,--whole-archive f1.a f2.a -o none/out.elf
RUN: ls none | sort | FileCheck %s --check-prefix=NONE
NONE-NOT:  {{^f[1-3]}}
NONE-NOT:  {{^}}.*\.native\.o{{$}}
NONE:      {{^}}f1.a(f1.o at [[#F1_OFFSET:]]).1.[[#%X,HEXPID:]].1.[[#PID:]].native.o.thinlto.bc{{$}}
NONE-NEXT: {{^}}f1.a(f1.o at [[#F1_OFFSET]]).1.[[#%X,HEXPID]].o{{$}}
NONE-NEXT: {{^}}f2.a(f2.o at [[#F2_OFFSET:]]).2.[[#%X,HEXPID]].2.[[#PID]].native.o.thinlto.bc{{$}}
NONE-NEXT: {{^}}f2.a(f2.o at [[#F2_OFFSET]]).2.[[#%X,HEXPID]].o{{$}}
NONE-NOT:  {{^f[1-3]}}

# 2. All of the backend compilations hit in the ThinLTO cache.
#
# Both f1.o and f2.o are satisfied from the ThinLTO cache. No backend
# compilation runs, so there should be no .native.o files, no .thinlto.bc files,
# and no extracted archive-member bitcode files.
RUN: mkdir all
RUN: %{link} -Wl,--whole-archive f1.a f2.a -o all/out.elf
RUN: ls all | sort | FileCheck %s --check-prefix=ALL
ALL-NOT: {{^f[1-3]}}
ALL-NOT: {{^}}.*\.native\.o{{$}}

# 3. Some backend compilations hit in the ThinLTO cache and some miss.
#
# f1.o and f2.o are cached, but the new f3.o misses the cache and imports
# from f1.o:
#   * f3.o must be compiled and extracted
#   * cached f1.o must be extracted because f3.o imports from it.
#   * cached f2.o should not be extracted or compiled.
RUN: %clang --target=x86_64-linux-gnu -O2 -flto=thin -c f3.c
RUN: llvm-ar rcs f3.a f3.o
RUN: mkdir some
RUN: %{link} -Wl,--whole-archive f1.a f2.a f3.a -o some/out.elf
RUN: ls some | sort | FileCheck %s --check-prefix=SOME
SOME-NOT:  {{^f[1-3]}}
SOME-NOT:  {{^}}.*\.native\.o{{$}}
SOME:      {{^}}f1.a(f1.o at [[#F1_OFFSET:]]).1.[[#%X,HEXPID:]].o{{$}}
SOME-NEXT: {{^}}f3.a(f3.o at [[#F3_OFFSET:]]).3.[[#%X,HEXPID]].3.[[#PID:]].native.o.thinlto.bc{{$}}
SOME-NEXT: {{^}}f3.a(f3.o at [[#F3_OFFSET]]).3.[[#%X,HEXPID]].o{{$}}
SOME-NOT:  {{^f[1-3]}}

#--- f1.c
__attribute__((retain)) int f1(int x) { return x; }

#--- f2.c
extern int f1(int);
__attribute__((retain)) int f2(int x) { return f1(x) + x; }

#--- f3.c
extern int f1(int);
__attribute__((retain)) int f3(int x) { return f1(x) + x; }