[PATCH 2/2 Resend] perf build: Support llvm and clang support compiled in

Thomas Richter
2023-07-25T15:05:43Z

Perf build suports llvm and clang support compiled in.
Test case 56 builtin clang support provides a test case
which is always skipped.

Link perf with the latest llvm and clang libraries and
enable this test case.

Use 'make LIBCLANGLLVM=1' to include this support.

V2: Add Library patch before -lclang-cpp

Output before:
# ./perf test 56
56: builtin clang support :
56.1: builtin clang compile C source to IR : Skip (not compiled in)
56.2: builtin clang compile C source to ELF object: \
Skip (not compiled in)

Output after:
# ./perf test 56
56: builtin clang support :
56.1: builtin clang compile C source to IR : Ok
56.2: builtin clang compile C source to ELF object : Ok
#

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>

From Ian Rogers
Build tested with LLVM 14 and 15 using:
BUILD_BPF_SKEL=1 LIBCLANGLLVM=1 LLVM_CONFIG=llvm-config-14
BUILD_BPF_SKEL=1 LIBCLANGLLVM=1 LLVM_CONFIG=llvm-config-15

Tested-by: Ian Rogers <irogers@google.com>
---
tools/perf/Makefile.config | 2 +-
tools/perf/Makefile.perf | 5 +----
2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index c5db0de49868..8e1d1fab9b4d 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -325,7 +325,7 @@ CORE_CFLAGS += -Wall
CORE_CFLAGS += -Wextra
CORE_CFLAGS += -std=gnu11

-CXXFLAGS += -std=gnu++14 -fno-exceptions -fno-rtti
+CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
CXXFLAGS += -Wall
CXXFLAGS += -fno-omit-frame-pointer
CXXFLAGS += -ggdb3
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 097316ef38e6..158a0733fc9d 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -426,10 +426,7 @@ EXTLIBS := $(call filter-out,$(EXCLUDE_EXTLIBS),$(EXTLIBS))
LIBS = -Wl,--whole-archive $(PERFLIBS) $(EXTRA_PERFLIBS) -Wl,--no-whole-archive -Wl,--start-group $(EXTLIBS) -Wl,--end-group

ifeq ($(USE_CLANG), 1)
- CLANGLIBS_LIST = AST Basic CodeGen Driver Frontend Lex Tooling Edit Sema Analysis Parse Serialization
- CLANGLIBS_NOEXT_LIST = $(foreach l,$(CLANGLIBS_LIST),$(shell $(LLVM_CONFIG) --libdir)/libclang$(l))
- LIBCLANG = $(foreach l,$(CLANGLIBS_NOEXT_LIST),$(wildcard $(l).a $(l).so))
- LIBS += -Wl,--start-group $(LIBCLANG) -Wl,--end-group
+ LIBS += -L$(shell $(LLVM_CONFIG) --libdir) -lclang-cpp
endif

ifeq ($(USE_LLVM), 1)
--
2.41.0