Andi Kleen <a...@firstfloor.org> writes:
> From: Andi Kleen <a...@linux.intel.com>
>
> [I posted this originally quite some time ago.
> This version fixes all review problems, particularly
> it works for C++ too and the test case really works.]
Ping!
Could someone please review it.
Note this might be obsolete with Honza's LTO option work, but if it's
not covered in his first iteration I would still have it earlier for the
Linux kernel LTO build (fixed ftrace)
-Andi
> This adds a new C/C++ option to force
> __attribute__((no_instrument_function)) on every function compiled.
>
> This is useful together with LTO. You may want to have the whole
> program compiled with -pg and have to specify that in the LTO
> link, but want to disable it for some specific files. As the
> option works on the frontend level it is already passed through
> properly by LTO.
>
> Without LTO it is equivalent to not specifing -pg or -mfentry.
>
> This fixes some missing functionality in the Linux kernel LTO port.
>
> Passed bootstrap and test suite on x86_64-linux. Ok?
>
> gcc/:
>
> 2013-08-10 Andi Kleen <a...@linux.intel.com>
>
> * c.opt (fno-instrument-function): Document.
>
> gcc/c:
>
> 2013-08-10 Andi Kleen <a...@linux.intel.com>
>
> * c-decl.c (start_function): Handle force_no_instrument_function
>
> gcc/cp:
>
> 2013-08-10 Andi Kleen <a...@linux.intel.com>
>
> * decl.c (start_preparsed_function): Handle
> force_no_instrument_function
>
> gcc/testsuite:
>
> 2013-08-10 Andi Kleen <a...@linux.intel.com>
>
> * g++.dg/fno-instrument-function.C: Add.
> * gcc.dg/fno-instrument-function.c: Add.
> ---
> gcc/c-family/c.opt | 4 ++++
> gcc/c/c-decl.c | 3 +++
> gcc/cp/decl.c | 3 +++
> gcc/doc/invoke.texi | 8 +++++++-
> gcc/testsuite/g++.dg/fno-instrument-function.C | 18 ++++++++++++++++++
> gcc/testsuite/gcc.dg/fno-instrument-function.c | 24 ++++++++++++++++++++++++
> 6 files changed, 59 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/g++.dg/fno-instrument-function.C
> create mode 100644 gcc/testsuite/gcc.dg/fno-instrument-function.c
>
> diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
> index 10ae84d..2159f89 100644
> --- a/gcc/c-family/c.opt
> +++ b/gcc/c-family/c.opt
> @@ -1014,6 +1014,10 @@ fnil-receivers
> ObjC ObjC++ Var(flag_nil_receivers) Init(1)
> Assume that receivers of Objective-C messages may be nil
>
> +fno-instrument-function
> +C C++ ObjC ObjC++ RejectNegative Report Var(force_no_instrument_function)
> +Force __attribute__((no_instrument_function)) for all functions in
> translation unit.
> +
> fnonansi-builtins
> C++ ObjC++ Var(flag_no_nonansi_builtin, 0)
>
> diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c
> index d9bbf5c..15717a9 100644
> --- a/gcc/c/c-decl.c
> +++ b/gcc/c/c-decl.c
> @@ -7876,6 +7876,9 @@ start_function (struct c_declspecs *declspecs, struct
> c_declarator *declarator,
> if (current_scope == file_scope)
> maybe_apply_pragma_weak (decl1);
>
> + if (force_no_instrument_function)
> + DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl1) = 1;
> +
> /* Warn for unlikely, improbable, or stupid declarations of `main'. */
> if (warn_main && MAIN_NAME_P (DECL_NAME (decl1)))
> {
> diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
> index 01804d2..103188b 100644
> --- a/gcc/cp/decl.c
> +++ b/gcc/cp/decl.c
> @@ -13023,6 +13023,9 @@ start_preparsed_function (tree decl1, tree attrs, int
> flags)
> && lookup_attribute ("noinline", attrs))
> warning (0, "inline function %q+D given attribute noinline", decl1);
>
> + if (force_no_instrument_function)
> + DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl1) = 1;
> +
> /* Handle gnu_inline attribute. */
> if (GNU_INLINE_P (decl1))
> {
> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> index 782b569..bc20a77 100644
> --- a/gcc/doc/invoke.texi
> +++ b/gcc/doc/invoke.texi
> @@ -169,7 +169,7 @@ in the following sections.
> -aux-info @var{filename} -fallow-parameterless-variadic-functions @gol
> -fno-asm -fno-builtin -fno-builtin-@var{function} @gol
> -fhosted -ffreestanding -fopenmp -fms-extensions -fplan9-extensions @gol
> --trigraphs -traditional -traditional-cpp @gol
> +-trigraphs -traditional -traditional-cpp -fno-instrument-function @gol
> -fallow-single-precision -fcond-mismatch -flax-vector-conversions @gol
> -fsigned-bitfields -fsigned-char @gol
> -funsigned-bitfields -funsigned-char}
> @@ -1868,6 +1868,12 @@ Allow implicit conversions between vectors with
> differing numbers of
> elements and/or incompatible element types. This option should not be
> used for new code.
>
> +@item -fno-instrument-function
> +@opindex fno-instrument-function
> +Override @option{-pg} for this translation unit. This is useful with
> +Link Time Optimization (LTO) to override the effects of -pg for a
> +specific source file.
> +
> @item -funsigned-char
> @opindex funsigned-char
> Let the type @code{char} be unsigned, like @code{unsigned char}.
> diff --git a/gcc/testsuite/g++.dg/fno-instrument-function.C
> b/gcc/testsuite/g++.dg/fno-instrument-function.C
> new file mode 100644
> index 0000000..e2f6518
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/fno-instrument-function.C
> @@ -0,0 +1,18 @@
> +/* Test -fno-instrument-function */
> +/* { dg-do compile } */
> +/* { dg-options "-pg -fno-instrument-function" } */
> +/* { dg-final { scan-assembler-not "mcount" } } */
> +/* Origin: Andi Kleen */
> +extern void foobar(const char *);
> +
> +void func(void)
> +{
> + foobar ("Hello world\n");
> +}
> +
> +void func2(void)
> +{
> + int i;
> + for (i = 0; i < 10; i++)
> + foobar ("Hello world");
> +}
> diff --git a/gcc/testsuite/gcc.dg/fno-instrument-function.c
> b/gcc/testsuite/gcc.dg/fno-instrument-function.c
> new file mode 100644
> index 0000000..9c68fa8
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/fno-instrument-function.c
> @@ -0,0 +1,24 @@
> +/* Test -fno-instrument-function */
> +/* { dg-do compile } */
> +/* { dg-options "-pg -fno-instrument-function" } */
> +/* { dg-final { scan-assembler-not "mcount" } } */
> +/* Origin: Andi Kleen */
> +extern void foobar(char *);
> +
> +void func(void)
> +{
> + foobar ("Hello world\n");
> +}
> +
> +void func2(void)
> +{
> + int i;
> + for (i = 0; i < 10; i++)
> + foobar ("Hello world");
> +}
> +
> +void func3(a)
> +char *a;
> +{
> + foobar("Hello world");
> +}
--
a...@linux.intel.com -- Speaking for myself only
