[PATCH] x86-64: Use R10 for profiling large model

[H.J. Lu via Gcc-patches]

Since R10 is preserved when calling mcount, R10 can be used a scratch
register to call mcount in large model.

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.
---
 gcc/config/i386/i386.c                    | 25 +++++++++++++++++++++--
 gcc/testsuite/gcc.target/i386/pr98482-1.c |  9 ++++++++
 gcc/testsuite/gcc.target/i386/pr98482-2.c |  9 ++++++++
 3 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pr98482-1.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pr98482-2.c

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index fad50e7e537..7a07ab8b5f5 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -20794,8 +20794,29 @@ x86_function_profiler (FILE *file, int labelno 
ATTRIBUTE_UNUSED)
       fprintf (file, "\tleaq\t%sP%d(%%rip),%%r11\n", LPREFIX, labelno);
 #endif
 
-      if (!TARGET_PECOFF && flag_pic)
-       fprintf (file, "1:\tcall\t*%s@GOTPCREL(%%rip)\n", mcount_name);
+      if (!TARGET_PECOFF)
+       {
+         switch (ix86_cmodel)
+           {
+           case CM_LARGE:
+             /* NB: R10 can be used as a scratch register here since
+                R10 is preserved when calling mcount.  */
+             fprintf (file, "1:\tmovabsq\t$%s, %%r10\n\tcall\t*%%r10\n",
+                      mcount_name);
+             break;
+           case CM_LARGE_PIC:
+             sorry ("profiling %<-mcmodel=large%> with PIC is not supported");
+             break;
+           case CM_SMALL_PIC:
+           case CM_MEDIUM_PIC:
+             fprintf (file, "1:\tcall\t*%s@GOTPCREL(%%rip)\n",
+                      mcount_name);
+             break;
+           default:
+             x86_print_call_or_nop (file, mcount_name);
+             break;
+           }
+       }
       else
        x86_print_call_or_nop (file, mcount_name);
     }
diff --git a/gcc/testsuite/gcc.target/i386/pr98482-1.c 
b/gcc/testsuite/gcc.target/i386/pr98482-1.c
new file mode 100644
index 00000000000..72d5ccb269c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr98482-1.c
@@ -0,0 +1,9 @@
+/* { dg-do compile { target { *-*-linux* && { ! ia32 } } } } */
+/* { dg-require-effective-target mfentry } */
+/* { dg-options "-fprofile -mfentry -O2 -mcmodel=large" } */
+/* { dg-final { scan-assembler "movabsq\t\\\$__fentry__, 
%r10\n\tcall\t\\*%r10" } } */
+
+void
+func (void)
+{
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr98482-2.c 
b/gcc/testsuite/gcc.target/i386/pr98482-2.c
new file mode 100644
index 00000000000..aed3ca4b6ff
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr98482-2.c
@@ -0,0 +1,9 @@
+/* { dg-do compile { target { *-*-linux* && { ! ia32 } } } } */
+/* { dg-require-effective-target mfentry } */
+/* { dg-require-effective-target fpic } */
+/* { dg-options "-fpic -fprofile -mfentry -O2 -mcmodel=large" } */
+
+void
+func (void)
+{
+} /* { dg-message "sorry, unimplemented: profiling '-mcmodel=large' with PIC 
is not supported" } */
-- 
2.29.2