lkml.org 
[lkml]   [2016]   [Sep]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 03/14] perf tools: Add feature detection for LLVM
    Date
    Check if basic LLVM compiling environment is ready.

    Use llvm-config to detect include and library directories. Avoid using
    'llvm-config --cxxflags' because its result contain some unwanted flags
    like --sysroot (if LLVM is built by yocto).

    Use '?=' to set LLVM_CONFIG, so explicitly passing LLVM_CONFIG to make
    would override it.

    Use 'llvm-config --libs BPF' to check if BPF backend is compiled in.
    Since now BPF bytecode is the only required backend, no need to waste
    time linking llvm and clang if BPF backend is missing. This
    also introduce an implicit requirement that LLVM should be new enough.
    Old LLVM doesn't support BPF backend.

    Signed-off-by: Wang Nan <wangnan0@huawei.com>
    Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
    Cc: Alexei Starovoitov <ast@fb.com>
    Cc: He Kuang <hekuang@huawei.com>
    Cc: Jiri Olsa <jolsa@kernel.org>
    ---
    tools/build/feature/Makefile | 8 ++++++++
    tools/build/feature/test-llvm.cpp | 8 ++++++++
    2 files changed, 16 insertions(+)
    create mode 100644 tools/build/feature/test-llvm.cpp

    diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
    index ac9c477..fd2f3e2 100644
    --- a/tools/build/feature/Makefile
    +++ b/tools/build/feature/Makefile
    @@ -54,6 +54,7 @@ FILES := $(addprefix $(OUTPUT),$(FILES))
    CC := $(CROSS_COMPILE)gcc -MD
    CXX := $(CROSS_COMPILE)g++ -MD
    PKG_CONFIG := $(CROSS_COMPILE)pkg-config
    +LLVM_CONFIG ?= llvm-config

    all: $(FILES)

    @@ -225,6 +226,13 @@ $(OUTPUT)test-sdt.bin:
    $(OUTPUT)test-cxx.bin:
    $(BUILDXX) -std=gnu++11

    +$(OUTPUT)test-llvm.bin:
    + $(BUILDXX) -std=gnu++11 \
    + -I$(shell $(LLVM_CONFIG) --includedir) \
    + -L$(shell $(LLVM_CONFIG) --libdir) \
    + $(shell $(LLVM_CONFIG) --libs Core BPF) \
    + $(shell $(LLVM_CONFIG) --system-libs)
    +
    -include $(OUTPUT)*.d

    ###############################
    diff --git a/tools/build/feature/test-llvm.cpp b/tools/build/feature/test-llvm.cpp
    new file mode 100644
    index 0000000..d8d2cee
    --- /dev/null
    +++ b/tools/build/feature/test-llvm.cpp
    @@ -0,0 +1,8 @@
    +#include "llvm/Support/ManagedStatic.h"
    +#include "llvm/Support/raw_ostream.h"
    +int main()
    +{
    + llvm::errs() << "Hello World!\n";
    + llvm::llvm_shutdown();
    + return 0;
    +}
    --
    1.8.3.4
    \
     
     \ /
      Last update: 2016-09-23 14:54    [W:4.120 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site