[parisc-linux] Oust HPPA PIC_OFFSET_TABLE_REGNUM_SAVED
Alan Modra
alan@linuxcare.com.au
Mon, 15 Jan 2001 22:09:30 +1100 (EST)
This patch rids us of PIC_OFFSET_TABLE_REGNUM_SAVED, and the problems that
go with it. Additionally, I reload the pic offset table register before
calls to guard against asm trashing r27/r19. Hasn't bootstrapped yet, but
looks promising. One possible fly in the ointment is whether any ABI
requires that r4 always be used to save the pic offset table reg.
* config/pa/pa.h (PIC_OFFSET_TABLE_REGNUM_SAVED): Remove.
(machine_function): Define.
(PIC_OFFSET_TABLE_SAVE_RTX) : Define.
(INIT_EXPANDERS): Define.
* config/pa/pa.c (pa_init_machine_status, pa_free_machine_status,
pa_init_expanders): New functions.
(hppa_expand_prologue): Use PIC_OFFSET_TABLE_SAVE_RTX instead of
PIC_OFFSET_TABLE_REGNUM_SAVED.
* config/pa/pa.md: Use PIC_OFFSET_TABLE_SAVE_RTX instead of
PIC_OFFSET_TABLE_REGNUM_SAVED throughout. Restore pic offset
table register before all calls as well as after.
* config/pa/pa32-regs.h (CONDITIONAL_REGISTER_USAGE): Remove
references to PIC_OFFSET_TABLE_REGNUM_SAVED.
* config/pa/pa64-regs.h (CONDITIONAL_REGISTER_USAGE): Likewise.
Alan Modra
--
Linuxcare. Support for the Revolution.
diff -urp -xCVS egcs/gcc/config/pa/pa.c newegcs/gcc/config/pa/pa.c
--- egcs/gcc/config/pa/pa.c Thu Jan 4 15:22:58 2001
+++ newegcs/gcc/config/pa/pa.c Mon Jan 15 20:54:01 2001
@@ -2918,6 +2918,40 @@ output_function_prologue (file, size)
remove_useless_addtr_insns (get_insns (), 0);
}
+/* Functions to initialize pic_offset_table_save_rtx.
+ These will be called, via pointer variables,
+ from push_function_context and pop_function_context. */
+
+static void
+pa_init_machine_status (p)
+ struct function *p;
+{
+ p->machine = (machine_function *) xmalloc (sizeof (machine_function));
+
+ p->machine->pic_offset_table_save_rtx = gen_reg_rtx (Pmode);
+}
+
+static void
+pa_free_machine_status (p)
+ struct function *p;
+{
+ if (p->machine == NULL)
+ return;
+
+ free (p->machine);
+ p->machine = NULL;
+}
+
+/* Do anything needed before RTL is emitted for each function. */
+
+void
+pa_init_expanders ()
+{
+ /* Arrange to save and restore machine status around nested functions. */
+ init_machine_status = pa_init_machine_status;
+ free_machine_status = pa_free_machine_status;
+}
+
void
hppa_expand_prologue()
{
@@ -3155,17 +3189,10 @@ hppa_expand_prologue()
So instead, we copy the PIC register into a reserved callee saved
register in the prologue. Then after each call we reload the PIC
- register from the callee saved register. We also reload the PIC
- register from the callee saved register in the epilogue ensure the
- PIC register is valid at function exit.
-
- This may (depending on the exact characteristics of the function)
- even be more efficient.
-
- Avoid this if the callee saved register wasn't used (these are
- leaf functions). */
- if (flag_pic && regs_ever_live[PIC_OFFSET_TABLE_REGNUM_SAVED])
- emit_move_insn (gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED),
+ register from the callee saved register. */
+
+ if (flag_pic && HARD_REGISTER_P (PIC_OFFSET_TABLE_SAVE_RTX))
+ emit_move_insn (PIC_OFFSET_TABLE_SAVE_RTX,
gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM));
}
Only in newegcs/gcc/config/pa: pa.c~
diff -urp -xCVS egcs/gcc/config/pa/pa.h newegcs/gcc/config/pa/pa.h
--- egcs/gcc/config/pa/pa.h Thu Jan 4 15:22:58 2001
+++ newegcs/gcc/config/pa/pa.h Mon Jan 15 20:54:01 2001
@@ -70,6 +70,14 @@ enum architecture_type
ARCHITECTURE_20
};
+struct rtx_def;
+/* A C structure for machine-specific, per-function data.
+ This is added to the cfun structure. */
+typedef struct machine_function
+{
+ struct rtx_def *pic_offset_table_save_rtx;
+} machine_function;
+
/* For -march= option. */
extern const char *pa_arch_string;
extern enum architecture_type pa_arch;
@@ -493,8 +501,8 @@ extern int target_flags;
#define PIC_OFFSET_TABLE_REG_CALL_CLOBBERED 1
/* Register into which we save the PIC_OFFEST_TABLE_REGNUM so that it
- can be restore across function calls. */
-#define PIC_OFFSET_TABLE_REGNUM_SAVED 4
+ can be restored across function calls. */
+#define PIC_OFFSET_TABLE_SAVE_RTX (cfun->machine->pic_offset_table_save_rtx)
#define DEFAULT_PCC_STRUCT_RETURN 0
@@ -854,6 +862,10 @@ extern enum cmp_type hppa_branch_type;
DELTA, target_name, DELTA); \
fprintf (FILE, "\n\t.EXIT\n\t.PROCEND\n"); \
}
+
+/* Initialize data used by insn expanders. This is called from
+ init_emit, once for each function, before code is generated. */
+#define INIT_EXPANDERS pa_init_expanders ()
/* This macro generates the assembly code for function entry.
FILE is a stdio stream to output the code to.
Only in newegcs/gcc/config/pa: pa.h~
diff -urp -xCVS egcs/gcc/config/pa/pa.md newegcs/gcc/config/pa/pa.md
--- egcs/gcc/config/pa/pa.md Mon Jan 8 22:47:00 2001
+++ newegcs/gcc/config/pa/pa.md Mon Jan 15 20:53:58 2001
@@ -5711,6 +5711,7 @@
emit_move_insn (arg_pointer_rtx,
gen_rtx_PLUS (word_mode, virtual_outgoing_args_rtx,
GEN_INT (64)));
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
/* Use two different patterns for calls to explicitly named functions
and calls through function pointers. This is necessary as these two
@@ -5735,18 +5736,12 @@
if (flag_pic)
{
use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn), pic_offset_table_rtx);
- use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn),
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
if (TARGET_64BIT)
use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn), arg_pointer_rtx);
/* After each call we must restore the PIC register, even if it
- doesn't appear to be used.
-
- This will set regs_ever_live for the callee saved register we
- stored the PIC register in. */
- emit_move_insn (pic_offset_table_rtx,
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
+ doesn't appear to be used. */
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
}
DONE;
}")
@@ -5888,6 +5883,8 @@
gen_rtx_PLUS (word_mode, virtual_outgoing_args_rtx,
GEN_INT (64)));
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
+
/* Use two different patterns for calls to explicitly named functions
and calls through function pointers. This is necessary as these two
types of calls use different calling conventions, and CSE might try
@@ -5915,18 +5912,12 @@
if (flag_pic)
{
use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn), pic_offset_table_rtx);
- use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn),
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
if (TARGET_64BIT)
use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn), arg_pointer_rtx);
/* After each call we must restore the PIC register, even if it
- doesn't appear to be used.
-
- This will set regs_ever_live for the callee saved register we
- stored the PIC register in. */
- emit_move_insn (pic_offset_table_rtx,
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
+ doesn't appear to be used. */
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
}
DONE;
}")
@@ -6090,22 +6081,18 @@
op = XEXP (operands[0], 0);
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
+
/* We do not allow indirect sibling calls. */
call_insn = emit_call_insn (gen_sibcall_internal_symref (op, operands[1]));
if (flag_pic)
{
use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn), pic_offset_table_rtx);
- use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn),
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
/* After each call we must restore the PIC register, even if it
- doesn't appear to be used.
-
- This will set regs_ever_live for the callee saved register we
- stored the PIC register in. */
- emit_move_insn (pic_offset_table_rtx,
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
+ doesn't appear to be used. */
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
}
DONE;
}")
@@ -6151,6 +6138,8 @@
op = XEXP (operands[1], 0);
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
+
/* We do not allow indirect sibling calls. */
call_insn = emit_call_insn (gen_sibcall_value_internal_symref (operands[0],
op,
@@ -6158,16 +6147,10 @@
if (flag_pic)
{
use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn), pic_offset_table_rtx);
- use_reg (&CALL_INSN_FUNCTION_USAGE (call_insn),
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
/* After each call we must restore the PIC register, even if it
- doesn't appear to be used.
-
- This will set regs_ever_live for the callee saved register we
- stored the PIC register in. */
- emit_move_insn (pic_offset_table_rtx,
- gen_rtx_REG (word_mode, PIC_OFFSET_TABLE_REGNUM_SAVED));
+ doesn't appear to be used. */
+ emit_move_insn (pic_offset_table_rtx, PIC_OFFSET_TABLE_SAVE_RTX);
}
DONE;
}")
Only in newegcs/gcc/config/pa: pa.md~
diff -urp -xCVS egcs/gcc/config/pa/pa32-regs.h newegcs/gcc/config/pa/pa32-regs.h
--- egcs/gcc/config/pa/pa32-regs.h Thu Jan 11 16:10:48 2001
+++ newegcs/gcc/config/pa/pa32-regs.h Mon Jan 15 18:22:39 2001
@@ -110,11 +110,7 @@
fixed_regs[i] = call_used_regs[i] = 1; \
} \
if (flag_pic) \
- { \
- fixed_regs[PIC_OFFSET_TABLE_REGNUM] = 1; \
- fixed_regs[PIC_OFFSET_TABLE_REGNUM_SAVED] = 1;\
- call_used_regs[PIC_OFFSET_TABLE_REGNUM_SAVED] = 1;\
- } \
+ fixed_regs[PIC_OFFSET_TABLE_REGNUM] = 1; \
}
/* Allocate the call used registers first. This should minimize
diff -urp -xCVS egcs/gcc/config/pa/pa64-regs.h newegcs/gcc/config/pa/pa64-regs.h
--- egcs/gcc/config/pa/pa64-regs.h Thu Jan 11 16:10:48 2001
+++ newegcs/gcc/config/pa/pa64-regs.h Mon Jan 15 18:22:40 2001
@@ -109,11 +109,7 @@ Boston, MA 02111-1307, USA. */
fixed_regs[i] = call_used_regs[i] = 1; \
} \
if (flag_pic) \
- { \
- fixed_regs[PIC_OFFSET_TABLE_REGNUM] = 1; \
- fixed_regs[PIC_OFFSET_TABLE_REGNUM_SAVED] = 1;\
- call_used_regs[PIC_OFFSET_TABLE_REGNUM_SAVED] = 1;\
- } \
+ fixed_regs[PIC_OFFSET_TABLE_REGNUM] = 1; \
}
/* Allocate the call used registers first. This should minimize