johannes 02/08/14 14:48:28
Modified: gcc/config darwin.c
gcc/config/rs6000 rs6000.c
Log:
Recompute current_function_uses_pic_offset_table at prologue. 3017416.
Revision Changes Path
1.75 +2 -8 gcc3/gcc/config/darwin.c
Index: darwin.c
===================================================================
RCS file: /cvs/Darwin/gcc3/gcc/config/darwin.c,v
retrieving revision 1.74
retrieving revision 1.75
diff -u -r1.74 -r1.75
--- darwin.c 2002/08/14 05:33:18 1.74
+++ darwin.c 2002/08/14 21:48:26 1.75
@@ -588,8 +588,7 @@
gen_rtx (HIGH, Pmode, offset)));
emit_insn (gen_rtx (SET, VOIDmode, reg,
gen_rtx (LO_SUM, Pmode, reg, offset)));
- emit_insn (gen_rtx (USE, VOIDmode,
- gen_rtx_REG (Pmode, PIC_OFFSET_TABLE_REGNUM)));
+ emit_insn (gen_rtx (USE, VOIDmode, pic_offset_table_rtx));
orig = gen_rtx (PLUS, Pmode, pic_offset_table_rtx, reg);
#endif
@@ -808,8 +807,7 @@
pic_ref = reg;
#else
- emit_insn (gen_rtx (USE, VOIDmode,
- gen_rtx_REG (Pmode, PIC_OFFSET_TABLE_REGNUM)));
+ emit_insn (gen_rtx (USE, VOIDmode, pic_offset_table_rtx));
emit_insn (gen_rtx (SET, VOIDmode, reg,
gen_rtx (HIGH, Pmode,
@@ -830,10 +828,6 @@
emit_move_insn (reg, pic);
pic = reg;
}
-#if 0
- emit_insn (gen_rtx (USE, VOIDmode,
- gen_rtx (REG, Pmode, PIC_OFFSET_TABLE_REGNUM)));
-#endif
pic_ref = gen_rtx (PLUS, Pmode,
pic,
1.166 +28 -0 gcc3/gcc/config/rs6000/rs6000.c
Index: rs6000.c
===================================================================
RCS file: /cvs/Darwin/gcc3/gcc/config/rs6000/rs6000.c,v
retrieving revision 1.165
retrieving revision 1.166
diff -u -r1.165 -r1.166
--- rs6000.c 2002/08/08 03:19:59 1.165
+++ rs6000.c 2002/08/14 21:48:27 1.166
@@ -11961,6 +11961,32 @@
&& (piclabel_name[2] == '+' || piclabel_name[2] == '-')));
}
+/* APPLE LOCAL recompute PIC register use */
+/* Sometimes a function has references that require the PIC register,
+ but optimization removes them all. To catch this case
+ recompute current_function_uses_pic_offset_table here.
+ This may allow us to eliminate the prologue and epilogue. */
+
+static int recompute_PIC_register_use ()
+{
+ if (DEFAULT_ABI == ABI_DARWIN
+ && flag_pic && current_function_uses_pic_offset_table
+ && !cfun->machine->ra_needs_full_frame)
+ {
+ rtx insn;
+ current_function_uses_pic_offset_table = 0;
+ push_topmost_sequence ();
+ for (insn = get_insns (); insn != NULL; insn = NEXT_INSN (insn))
+ if ( reg_mentioned_p (pic_offset_table_rtx, insn))
+ {
+ current_function_uses_pic_offset_table = 1;
+ break;
+ }
+ pop_topmost_sequence ();
+ }
+ return 0;
+}
+
/* APPLE LOCAL volatile pic base reg in leaves */
/* If this is a leaf function and we used any pic-based references,
see if there is an unused volatile reg we can use instead of R31.
@@ -12092,6 +12118,8 @@
void
rs6000_emit_prologue ()
{
+ /* APPLE LOCAL recompute PIC register use */
+ int dummy ATTRIBUTE_UNUSED = recompute_PIC_register_use ();
/* APPLE LOCAL volatile pic base reg in leaves */
int ignored ATTRIBUTE_UNUSED = try_leaf_pic_optimization ();
rs6000_stack_t *info = rs6000_stack_info ();
