* pa-linux.h (TARGET_HAS_STUBS_AND_ELF_SECTIONS): Delete define.

	* pa32-linux.h (FUNCTION_OK_FOR_SIBCALL): Delete define.
	* pa.c (pa_function_ok_for_sibcall): Allow non indirect sibcalls on
	TARGET_ELF32.  Add comment on sibcall issues for TARGET_64BIT.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@60377 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 19 insertions, 20 deletions

diff --git a/gcc/config/pa/pa-linux.h b/gcc/config/pa/pa-linux.h
index a39ef318a00..b2c09981689 100644
--- a/gcc/config/pa/pa-linux.h
+++ b/gcc/config/pa/pa-linux.h
@@ -167,11 +167,6 @@ Boston, MA 02111-1307, USA.  */
 /* Globalizing directive for a label.  */
 #define GLOBAL_ASM_OP ".globl "
 
-/* This definition is used inside pa.c to disable all
-   sibcall optimization, because sibcalls, stubs and
-   elf sections don't play well.  */
-#define TARGET_HAS_STUBS_AND_ELF_SECTIONS 1
-
 /* FIXME: Hacked from the <elfos.h> one so that we avoid multiple
    labels in a function declaration (since pa.c seems determined to do
    it differently)  */
diff --git a/gcc/config/pa/pa.c b/gcc/config/pa/pa.c
index cd52977abb6..651fc96eb37 100644
--- a/gcc/config/pa/pa.c
+++ b/gcc/config/pa/pa.c
@@ -6878,14 +6878,26 @@ pa_function_ok_for_sibcall (decl, exp)
      tree decl;
      tree exp ATTRIBUTE_UNUSED;
 {
-#ifdef TARGET_HAS_STUBS_AND_ELF_SECTIONS
-  /* Sibcalls, stubs, and elf sections don't play well.  */
-  return false;
-#endif
+  /* Sibcalls are ok for TARGET_ELF32 as along as the linker is used in
+     single subspace mode and the call is not indirect.  As far as I know,
+     there is no operating system support for the multiple subspace mode.
+     It might be possible to support indirect calls if we didn't use
+     $$dyncall (see the indirect sequence generated in output_call).  */
+  if (TARGET_ELF32)
+    return (decl != NULL_TREE);
+
+  /* Sibcalls are not ok because the arg pointer register is not a fixed
+     register.  This prevents the sibcall optimization from occuring.  In
+     addition, there are problems with stub placement using GNU ld.  This
+     is because a normal sibcall branch uses a 17-bit relocation while
+     a regular call branch uses a 22-bit relocation.  As a result, more
+     care needs to be taken in the placement of long-branch stubs.  */
+  if (TARGET_64BIT)
+    return false;
+
   return (decl
-	  && ! TARGET_PORTABLE_RUNTIME
-	  && ! TARGET_64BIT
-	  && ! TREE_PUBLIC (decl));
+	  && !TARGET_PORTABLE_RUNTIME
+	  && !TREE_PUBLIC (decl));
 }
 
 /* Returns 1 if the 6 operands specified in OPERANDS are suitable for
diff --git a/gcc/config/pa/pa32-linux.h b/gcc/config/pa/pa32-linux.h
index e8bc78322ee..c8e7b37012b 100644
--- a/gcc/config/pa/pa32-linux.h
+++ b/gcc/config/pa/pa32-linux.h
@@ -22,14 +22,6 @@ Boston, MA 02111-1307, USA.  */
 #undef TARGET_ELF32
 #define TARGET_ELF32 1
 
-/* Sibcalls are ok when ld is used in single subspace mode.  The
-   multiple subspace mode is not compatible with sibcalls to external
-   functions because the linker generated stubs store the return
-   pointer into the frame.  This target does not need multiple
-   subspace stubs, so we allow sibcalls to all functions.  */
-#undef FUNCTION_OK_FOR_SIBCALL
-#define FUNCTION_OK_FOR_SIBCALL(DECL) 1
-
 /* The libcall __canonicalize_funcptr_for_compare is referenced in
    crtend.o and the reference isn't resolved in objects that don't
    compare function pointers.  Thus, we need to play games to provide