On Fri, Jan 8, 2021 at 4:50 AM H.J. Lu <hjl.to...@gmail.com> wrote: > > On Fri, Jan 8, 2021 at 1:24 AM Uros Bizjak <ubiz...@gmail.com> wrote: > > > > > Since R10 is preserved when calling mcount, R10 can be used a scratch > > > register to call mcount in large model. > > > > Please mention that R10 can be used as a static chain registers and is > > preserved when calling mcount for nested functions. > > > > > gcc/ > > > > > > PR target/98482 > > > * config/i386/i386.c (x86_function_profiler): Use R10 to call > > > mcount in large model. Sorry for large model with PIC. > > > > > > gcc/testsuite/ > > > > > > PR target/98482 > > > * gcc.target/i386/pr98482-1.c: New test. > > > * gcc.target/i386/pr98482-1.c: Likewise. > > > > OK with comment fixes. > > > > Thanks, > > Uros. > > > > + case CM_LARGE: > > + /* NB: R10 can be used as a scratch register here since > > + R10 is preserved when calling mcount. */ > > > > Also mention that R10 can be used as a static chain register and is > > preserved when calling mcount for nested functions. > > > > + fprintf (file, "1:\tmovabsq\t$%s, %%r10\n\tcall\t*%%r10\n", > > + mcount_name); > > + break; > > This is the patch I am checking in. >
For NO_PROFILE_COUNTERS targets, R11 is a scratch register. We can use R10 and R11 to call mcount in large model with PIC. OK for master? Thanks. -- H.J.
From b2e0bccbdba630a1f7f8b601e19b7302e375e240 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" <hjl.to...@gmail.com> Date: Fri, 8 Jan 2021 05:20:19 -0800 Subject: [PATCH] x86-64: Use R10 and R11 for profiling large model with PIC For NO_PROFILE_COUNTERS targets, R11 is a scratch register. We can use R10 and R11 to call mcount in large model with PIC. gcc/ PR target/98482 * config/i386/i386.c (x86_function_profiler): Use R10 and R11 to call mcount in large model with PIC for NO_PROFILE_COUNTERS targets. gcc/testsuite/ PR target/98482 * gcc.target/i386/pr98482-2.c: Updated. --- gcc/config/i386/i386.c | 10 ++++++++++ gcc/testsuite/gcc.target/i386/pr98482-2.c | 3 ++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index d3068462fcd..50380865acd 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -20806,7 +20806,17 @@ x86_function_profiler (FILE *file, int labelno ATTRIBUTE_UNUSED) mcount_name); break; case CM_LARGE_PIC: +#ifdef NO_PROFILE_COUNTERS + fprintf (file, "1:\tmovabsq\t$_GLOBAL_OFFSET_TABLE_-1b, %%r11\n"); + fprintf (file, "\tleaq\t1b(%%rip), %%r10\n"); + fprintf (file, "\taddq\t%%r11, %%r10\n"); + fprintf (file, "\tmovabsq\t$%s@PLTOFF, %%r11\n", + mcount_name); + fprintf (file, "\taddq\t%%r11, %%r10\n"); + fprintf (file, "\tcall\t*%%r10\n"); +#else sorry ("profiling %<-mcmodel=large%> with PIC is not supported"); +#endif break; case CM_SMALL_PIC: case CM_MEDIUM_PIC: diff --git a/gcc/testsuite/gcc.target/i386/pr98482-2.c b/gcc/testsuite/gcc.target/i386/pr98482-2.c index aed3ca4b6ff..0ee142db12c 100644 --- a/gcc/testsuite/gcc.target/i386/pr98482-2.c +++ b/gcc/testsuite/gcc.target/i386/pr98482-2.c @@ -2,8 +2,9 @@ /* { dg-require-effective-target mfentry } */ /* { dg-require-effective-target fpic } */ /* { dg-options "-fpic -fprofile -mfentry -O2 -mcmodel=large" } */ +/* { dg-final { scan-assembler "movabsq\t\\\$__fentry__@PLTOFF, %r11\n\taddq\t%r11, %r10\n\tcall\t\\*%r10" } } */ void func (void) { -} /* { dg-message "sorry, unimplemented: profiling '-mcmodel=large' with PIC is not supported" } */ +} -- 2.29.2