* regs.h (HARD_REGNO_CALLER_SAVE_MODE): New macro.

        * caller-save.c (init_caller_save): Use it.
        * tm.texi: Document HARD_REGNO_CALLER_SAVE_MODE.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@22682 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 48e72c0..5e224d7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,4 +1,10 @@
-Wed Sep 30 12:57:30 1998Zack Weinberg  <zack@rabi.phys.columbia.edu>  
+Wed Sep 30 18:19:27 1998  Michael Hayes  <m.hayes@elec.canterbury.ac.nz>
+
+       * regs.h (HARD_REGNO_CALLER_SAVE_MODE): New macro.
+       * caller-save.c (init_caller_save): Use it.
+       * tm.texi: Document HARD_REGNO_CALLER_SAVE_MODE.
+
+Wed Sep 30 12:57:30 1998 Zack Weinberg  <zack@rabi.phys.columbia.edu>  
 
        * configure.in: Add --enable-cpplib option which uses cpplib
        for cpp, but doesn't link cpplib into cc1.  Make help text

diff --git a/gcc/caller-save.c b/gcc/caller-save.c
index 4a2deb6..60011f7 100644 (file)
--- a/gcc/caller-save.c
+++ b/gcc/caller-save.c
@@ -115,7 +115,7 @@ init_caller_save ()
        {
          for (j = 1; j <= MOVE_MAX / UNITS_PER_WORD; j++)
            {
-             regno_save_mode[i][j] = choose_hard_reg_mode (i, j);
+             regno_save_mode[i][j] = HARD_REGNO_CALLER_SAVE_MODE (i, j);
              if (regno_save_mode[i][j] == VOIDmode && j == 1)
                {
                  call_fixed_regs[i] = 1;

diff --git a/gcc/regs.h b/gcc/regs.h
index e248665..02bdf92 100644 (file)
--- a/gcc/regs.h
+++ b/gcc/regs.h
@@ -211,6 +211,12 @@ extern int caller_save_needed;
 #define CLASS_LIKELY_SPILLED_P(CLASS) (reg_class_size[(int) (CLASS)] == 1)
 #endif
 
+/* Select a register mode required for caller save of hard regno REGNO.  */
+#ifndef HARD_REGNO_CALLER_SAVE_MODE
+#define HARD_REGNO_CALLER_SAVE_MODE(REGNO, NREGS) \
+  choose_hard_reg_mode (REGNO, NREGS)
+#endif
+
 /* Allocated in local_alloc.  */
 
 /* A list of SCRATCH rtl allocated by local-alloc.  */

diff --git a/gcc/tm.texi b/gcc/tm.texi
index ea3e8b3..a42eb67 100644 (file)
--- a/gcc/tm.texi
+++ b/gcc/tm.texi
@@ -3174,6 +3174,14 @@ this is worth doing, and 0 otherwise.
 
 If you don't define this macro, a default is used which is good on most
 machines: @code{4 * @var{calls} < @var{refs}}.
+
+@findex HARD_REGNO_CALLER_SAVE_MODE
+@item HARD_REGNO_CALLER_SAVE_MODE (@var{regno}, @var{nregs})
+A C expression specifying which mode is required for saving @var{nregs}
+of a pseudo-register in call-clobbered hard register @var{regno}.  If
+@var{regno} is unsuitable for caller save, @code{VOIDmode} should be
+returned.  For most machines this macro need not be defined since GCC
+will select the smallest suitable mode.
 @end table
 
 @node Function Entry