Hi,
Thanks for the review.
On Tue, 5 Nov 2019 at 03:57, H.J. Lu <[email protected]> wrote:
>
> On Sun, Nov 3, 2019 at 6:45 PM Kugan Vivekanandarajah
> <[email protected]> wrote:
> >
> > Thanks for the reviews.
> >
> >
> > On Sat, 2 Nov 2019 at 02:49, H.J. Lu <[email protected]> wrote:
> > >
> > > On Thu, Oct 31, 2019 at 6:33 PM Kugan Vivekanandarajah
> > > <[email protected]> wrote:
> > > >
> > > > On Wed, 30 Oct 2019 at 03:11, H.J. Lu <[email protected]> wrote:
> > > > >
> > > > > On Sun, Oct 27, 2019 at 6:33 PM Kugan Vivekanandarajah
> > > > > <[email protected]> wrote:
> > > > > >
> > > > > > Hi Richard,
> > > > > >
> > > > > > Thanks for the review.
> > > > > >
> > > > > > On Wed, 23 Oct 2019 at 23:07, Richard Biener
> > > > > > <[email protected]> wrote:
> > > > > > >
> > > > > > > On Mon, Oct 21, 2019 at 10:04 AM Kugan Vivekanandarajah
> > > > > > > <[email protected]> wrote:
> > > > > > > >
> > > > > > > > Hi Richard,
> > > > > > > >
> > > > > > > > Thanks for the pointers.
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > > On Fri, 11 Oct 2019 at 22:33, Richard Biener
> > > > > > > > <[email protected]> wrote:
> > > > > > > > >
> > > > > > > > > On Fri, Oct 11, 2019 at 6:15 AM Kugan Vivekanandarajah
> > > > > > > > > <[email protected]> wrote:
> > > > > > > > > >
> > > > > > > > > > Hi Richard,
> > > > > > > > > > Thanks for the review.
> > > > > > > > > >
> > > > > > > > > > On Wed, 2 Oct 2019 at 20:41, Richard Biener
> > > > > > > > > > <[email protected]> wrote:
> > > > > > > > > > >
> > > > > > > > > > > On Wed, Oct 2, 2019 at 10:39 AM Kugan Vivekanandarajah
> > > > > > > > > > > <[email protected]> wrote:
> > > > > > > > > > > >
> > > > > > > > > > > > Hi,
> > > > > > > > > > > >
> > > > > > > > > > > > As mentioned in the PR, attached patch adds
> > > > > > > > > > > > COLLECT_AS_OPTIONS for
> > > > > > > > > > > > passing assembler options specified with -Wa, to the
> > > > > > > > > > > > link-time driver.
> > > > > > > > > > > >
> > > > > > > > > > > > The proposed solution only works for uniform -Wa
> > > > > > > > > > > > options across all
> > > > > > > > > > > > TUs. As mentioned by Richard Biener, supporting
> > > > > > > > > > > > non-uniform -Wa flags
> > > > > > > > > > > > would require either adjusting partitioning according
> > > > > > > > > > > > to flags or
> > > > > > > > > > > > emitting multiple object files from a single LTRANS
> > > > > > > > > > > > CU. We could
> > > > > > > > > > > > consider this as a follow up.
> > > > > > > > > > > >
> > > > > > > > > > > > Bootstrapped and regression tests on arm-linux-gcc. Is
> > > > > > > > > > > > this OK for trunk?
> > > > > > > > > > >
> > > > > > > > > > > While it works for your simple cases it is unlikely to
> > > > > > > > > > > work in practice since
> > > > > > > > > > > your implementation needs the assembler options be
> > > > > > > > > > > present at the link
> > > > > > > > > > > command line. I agree that this might be the way for
> > > > > > > > > > > people to go when
> > > > > > > > > > > they face the issue but then it needs to be documented
> > > > > > > > > > > somewhere
> > > > > > > > > > > in the manual.
> > > > > > > > > > >
> > > > > > > > > > > That is, with COLLECT_AS_OPTION (why singular? I'd
> > > > > > > > > > > expected
> > > > > > > > > > > COLLECT_AS_OPTIONS) available to cc1 we could stream this
> > > > > > > > > > > string
> > > > > > > > > > > to lto_options and re-materialize it at link time (and
> > > > > > > > > > > diagnose mismatches
> > > > > > > > > > > even if we like).
> > > > > > > > > > OK. I will try to implement this. So the idea is if we
> > > > > > > > > > provide
> > > > > > > > > > -Wa,options as part of the lto compile, this should be
> > > > > > > > > > available
> > > > > > > > > > during link time. Like in:
> > > > > > > > > >
> > > > > > > > > > arm-linux-gnueabihf-gcc -march=armv7-a -mthumb -O2 -flto
> > > > > > > > > > -Wa,-mimplicit-it=always,-mthumb -c test.c
> > > > > > > > > > arm-linux-gnueabihf-gcc -flto test.o
> > > > > > > > > >
> > > > > > > > > > I am not sure where should we stream this. Currently,
> > > > > > > > > > cl_optimization
> > > > > > > > > > has all the optimization flag provided for compiler and it
> > > > > > > > > > is
> > > > > > > > > > autogenerated and all the flags are integer values. Do you
> > > > > > > > > > have any
> > > > > > > > > > preference or example where this should be done.
> > > > > > > > >
> > > > > > > > > In lto_write_options, I'd simply append the contents of
> > > > > > > > > COLLECT_AS_OPTIONS
> > > > > > > > > (with -Wa, prepended to each of them), then recover them in
> > > > > > > > > lto-wrapper
> > > > > > > > > for each TU and pass them down to the LTRANS compiles (if
> > > > > > > > > they agree
> > > > > > > > > for all TUs, otherwise I'd warn and drop them).
> > > > > > > >
> > > > > > > > Attached patch streams it and also make sure that the options
> > > > > > > > are the
> > > > > > > > same for all the TUs. Maybe it is a bit restrictive.
> > > > > > > >
> > > > > > > > What is the best place to document COLLECT_AS_OPTIONS. We don't
> > > > > > > > seem
> > > > > > > > to document COLLECT_GCC_OPTIONS anywhere ?
> > > > > > >
> > > > > > > Nowhere, it's an implementation detail then.
> > > > > > >
> > > > > > > > Attached patch passes regression and also fixes the original ARM
> > > > > > > > kernel build issue with tumb2.
> > > > > > >
> > > > > > > Did you try this with multiple assembler options? I see you
> > > > > > > stream
> > > > > > > them as -Wa,-mfpu=xyz,-mthumb but then compare the whole
> > > > > > > option strings so a mismatch with -Wa,-mthumb,-mfpu=xyz would be
> > > > > > > diagnosed. If there's a spec induced -Wa option do we get to see
> > > > > > > that as well? I can imagine -march=xyz enabling a -Wa option
> > > > > > > for example.
> > > > > > >
> > > > > > > + *collect_as = XNEWVEC (char, strlen (args_text) +
> > > > > > > 1);
> > > > > > > + strcpy (*collect_as, args_text);
> > > > > > >
> > > > > > > there's strdup. Btw, I'm not sure why you don't simply leave
> > > > > > > the -Wa option in the merged options [individually] and match
> > > > > > > them up but go the route of comparing strings and carrying that
> > > > > > > along separately. I think that would be much better.
> > > > > >
> > > > > > Is attached patch which does this is OK?
> > > > > >
> > > > >
> > > > > Don't you need to also handle -Xassembler? Since -Wa, doesn't work
> > > > > with comma in
> > > > > assembler options, like -mfoo=foo1,foo2, one needs to use
> > > > >
> > > > > -Xassembler -mfoo=foo1,foo2
> > > > >
> > > > > to pass -mfoo=foo1,foo2 to assembler.
> > > >
> > > >
> > > > gcc -flto -O2 -Wa,-mcpu=zzz1 -mcpu=xxx1 -c foo.c
> > > > gcc -flto -O2 -Wa,-mcpu=zzz2 -mcpu=xxx2 -c bar.c
> > > >
> > > > What should be the option we should provide for the final
> > > > gcc -flto foo.o bar.o -o out
> > > >
> > > > I think our ultimate aim is to handle this in LTO partitioning. That
> > > > is, we should create partitioning such that each partition has the
> > > > same -Wa options. This could also handle -Xassembler -mfoo=foo1,foo2
> > > > which H.J. Lu wanted. We need to modify the heuristics and do some
> > > > performance testing.
> > > >
> > > > In the meantime we could push a simpler solution which is to accept
> > > > -Wa option if they are identical. This would fix at least some of the
> > > > reported cases. Trying to work out what is compatible options, even if
> > > > we ask the back-end to do this, is not a straightforward strategy and
> > > > can be a maintenance nightmare. Unless we can query GNU AS somehow. If
> > > > I am missing something please let me know.
> > >
> > > +/* Store switches specified for as with -Wa in COLLECT_AS_OPTIONS
> > > + and place that in the environment. */
> > > +static void
> > > +putenv_COLLECT_AS_OPTIONS (vec<char_p> vec)
> > > +{
> > > + unsigned ix;
> > > + char *opt;
> > > + int len = vec.length ();
> > > +
> > > + if (!len)
> > > + return;
> > > +
> > > + obstack_init (&collect_obstack);
> > > + obstack_grow (&collect_obstack, "COLLECT_AS_OPTIONS=",
> > > + sizeof ("COLLECT_AS_OPTIONS=") - 1);
> > > + obstack_grow (&collect_obstack, "-Wa,", strlen ("-Wa,"));
> > > +
> > > + FOR_EACH_VEC_ELT (vec, ix, opt)
> > > + {
> > > + obstack_grow (&collect_obstack, opt, strlen (opt));
> > > + --len;
> > > + if (len)
> > > + obstack_grow (&collect_obstack, ",", strlen (","));
> > > + }
> > > +
> > > + xputenv (XOBFINISH (&collect_obstack, char *));
> > >
> > > This missed the null terminator.
> >
> > Attached patch addresses the review comments I got so far.
> >
>
> + if (len)
> + obstack_grow (&collect_obstack, ",", strlen (","));
>
> Why not sizeof (",") - 1?
I guess I copied and pasted it from elsewhere else. We seem to use
both. I have changed it now.
>
> diff --git a/gcc/lto-wrapper.c b/gcc/lto-wrapper.c
> index 9a7bbd0c022..148c52906d1 100644
> --- a/gcc/lto-wrapper.c
> +++ b/gcc/lto-wrapper.c
> @@ -253,6 +253,11 @@ merge_and_complain (struct cl_decoded_option
> **decoded_options,
> break;
>
> default:
> + if (foption->opt_index == OPT_Wa_)
> + {
> + append_option (decoded_options, decoded_options_count, foption);
> + break;
> + }
> if (!(cl_options[foption->opt_index].flags & CL_TARGET))
> break;
>
> Why not use "case OPT_Wa_:" here?
Done.
>
> For
>
> + static const char *collect_as;
> + for (unsigned int j = 1; j < count; ++j)
> + {
> + struct cl_decoded_option *option = &opts[j];
> + if (j == 1)
> + collect_as = NULL;
>
> why not simply
>
> const char *collect_as = NULL?
I wanted to make sure that if we call this from multiple places, it
still works. I guess it is still going to be the same. I have changed
it now as you have suggested.
Is this revised patch OK? I will do a fresh bootstrap and regression
testing before committing.
Thanks,
Kugan
>
>
> H.J.
From 72fb068367b67a9b866eb3658739c59b222a1a42 Mon Sep 17 00:00:00 2001
From: Kugan <[email protected]>
Date: Sat, 28 Sep 2019 02:11:49 +1000
Subject: [PATCH] COLLECT_AS support
Change-Id: I52c46d1fc30e51c77cc5a41b8780f252e20bdd86
---
gcc/gcc.c | 29 +++++++++++++++++++++
gcc/lto-opts.c | 16 ++++++++++--
gcc/lto-wrapper.c | 32 ++++++++++++++++++++++++
gcc/testsuite/gcc.target/arm/pr78353-1.c | 9 +++++++
gcc/testsuite/gcc.target/arm/pr78353-2.c | 9 +++++++
5 files changed, 93 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/arm/pr78353-1.c
create mode 100644 gcc/testsuite/gcc.target/arm/pr78353-2.c
diff --git a/gcc/gcc.c b/gcc/gcc.c
index 1216cdd505a..3c51e5c5f69 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -5239,6 +5239,34 @@ do_specs_vec (vec<char_p> vec)
}
}
+/* Store switches specified for as with -Wa in COLLECT_AS_OPTIONS
+ and place that in the environment. */
+static void
+putenv_COLLECT_AS_OPTIONS (vec<char_p> vec)
+{
+ unsigned ix;
+ char *opt;
+ int len = vec.length ();
+
+ if (!len)
+ return;
+
+ obstack_init (&collect_obstack);
+ obstack_grow (&collect_obstack, "COLLECT_AS_OPTIONS=-Wa,",
+ sizeof ("COLLECT_AS_OPTIONS=-Wa,") - 1);
+
+ FOR_EACH_VEC_ELT (vec, ix, opt)
+ {
+ obstack_grow (&collect_obstack, opt, strlen (opt));
+ --len;
+ if (len)
+ obstack_grow (&collect_obstack, ",", sizeof (",") - 1);
+ }
+
+ obstack_1grow (&collect_obstack, '\0');
+ xputenv (XOBFINISH (&collect_obstack, char *));
+}
+
/* Process the sub-spec SPEC as a portion of a larger spec.
This is like processing a whole spec except that we do
not initialize at the beginning and we do not supply a
@@ -7360,6 +7388,7 @@ driver::main (int argc, char **argv)
global_initializations ();
build_multilib_strings ();
set_up_specs ();
+ putenv_COLLECT_AS_OPTIONS (assembler_options);
putenv_COLLECT_GCC (argv[0]);
maybe_putenv_COLLECT_LTO_WRAPPER ();
maybe_putenv_OFFLOAD_TARGETS ();
diff --git a/gcc/lto-opts.c b/gcc/lto-opts.c
index 0e9f24e1189..d89fe5cc4f9 100644
--- a/gcc/lto-opts.c
+++ b/gcc/lto-opts.c
@@ -166,8 +166,20 @@ lto_write_options (void)
obstack_grow (&temporary_obstack, "\0", 1);
args = XOBFINISH (&temporary_obstack, char *);
lto_write_data (args, strlen (args) + 1);
- lto_end_section ();
-
obstack_free (&temporary_obstack, NULL);
+ const char *collect_as_options = getenv ("COLLECT_AS_OPTIONS");
+
+ if (collect_as_options)
+ {
+ obstack_init (&temporary_obstack);
+ append_to_collect_gcc_options (&temporary_obstack, &first_p,
+ collect_as_options);
+ obstack_grow (&temporary_obstack, "\0", 1);
+ args = XOBFINISH (&temporary_obstack, char *);
+ lto_write_data (args, strlen (args) + 1);
+ obstack_free (&temporary_obstack, NULL);
+ }
+
+ lto_end_section ();
free (section_name);
}
diff --git a/gcc/lto-wrapper.c b/gcc/lto-wrapper.c
index 9a7bbd0c022..e55b1d64cfd 100644
--- a/gcc/lto-wrapper.c
+++ b/gcc/lto-wrapper.c
@@ -252,6 +252,10 @@ merge_and_complain (struct cl_decoded_option **decoded_options,
case OPT_SPECIAL_input_file:
break;
+ case OPT_Wa_:
+ append_option (decoded_options, decoded_options_count, foption);
+ break;
+
default:
if (!(cl_options[foption->opt_index].flags & CL_TARGET))
break;
@@ -574,6 +578,30 @@ parse_env_var (const char *str, char ***pvalues, const char *append)
return num;
}
+/* Append options OPTS from -Wa, options to ARGV_OBSTACK. */
+
+static void
+append_compiler_wa_options (obstack *argv_obstack,
+ struct cl_decoded_option *opts,
+ unsigned int count)
+{
+ static const char *collect_as = NULL;
+ for (unsigned int j = 1; j < count; ++j)
+ {
+ struct cl_decoded_option *option = &opts[j];
+ if (option->opt_index != OPT_Wa_)
+ continue;
+ const char *args_text = option->orig_option_with_args_text;
+ /* We expect all the -Wa, options to be same. */
+ if (collect_as && strcmp (collect_as, args_text) != 0)
+ fatal_error (input_location, "-Wa, options does not match");
+ if (!collect_as)
+ {
+ obstack_ptr_grow (argv_obstack, args_text);
+ collect_as = args_text;
+ }
+ }
+}
/* Append options OPTS from lto or offload_lto sections to ARGV_OBSTACK. */
static void
@@ -846,6 +874,8 @@ compile_offload_image (const char *target, const char *compiler_path,
/* Append options from offload_lto sections. */
append_compiler_options (&argv_obstack, compiler_opts,
compiler_opt_count);
+ append_compiler_wa_options (&argv_obstack, compiler_opts,
+ compiler_opt_count);
append_diag_options (&argv_obstack, linker_opts, linker_opt_count);
/* Append options specified by -foffload last. In case of conflicting
@@ -1349,6 +1379,8 @@ run_gcc (unsigned argc, char *argv[])
append_compiler_options (&argv_obstack, fdecoded_options,
fdecoded_options_count);
+ append_compiler_wa_options (&argv_obstack, fdecoded_options,
+ fdecoded_options_count);
append_linker_options (&argv_obstack, decoded_options, decoded_options_count);
/* Scan linker driver arguments for things that are of relevance to us. */
diff --git a/gcc/testsuite/gcc.target/arm/pr78353-1.c b/gcc/testsuite/gcc.target/arm/pr78353-1.c
new file mode 100644
index 00000000000..bba81ee50c3
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/pr78353-1.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-march=armv7-a -mthumb -O2 -flto -Wa,-mimplicit-it=always" } */
+
+int main(int x)
+{
+ asm("teq %0, #0; addne %0, %0, #1" : "=r" (x));
+ return x;
+}
+
diff --git a/gcc/testsuite/gcc.target/arm/pr78353-2.c b/gcc/testsuite/gcc.target/arm/pr78353-2.c
new file mode 100644
index 00000000000..776eb64b8c7
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/pr78353-2.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-march=armv7-a -mthumb -O2 -flto -Wa,-mimplicit-it=always,-mthumb" } */
+
+int main(int x)
+{
+ asm("teq %0, #0; addne %0, %0, #1" : "=r" (x));
+ return x;
+}
+
--
2.17.1
