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sh-hms: simplify operands of constant addresses with MINUSes
- To: gcc-patches at gcc dot gnu dot org
- Subject: sh-hms: simplify operands of constant addresses with MINUSes
- From: Alexandre Oliva <aoliva at redhat dot com>
- Date: 08 Nov 2000 02:26:10 -0200
- Organization: GCC Team, Red Hat
It seems that some of the changes to introduce PIC support on sh-elf
broke sh-hms. The replacement output_addr_const wouldn't simplify
MINUS expressions, which would cause GCC to sometimes output assembly
constants such as `s + 5 - s', for which the assembler couldn't
generate relocations, for not knowing in which segment `s' would live.
Instead of moving the simplification over to
sh.c:output_pic_addr_const(), I decided to make the generic
output_addr_const() usable for SH PIC. Since the PIC implementation
on the SH uses a couple of unspecs within relatively complex
expressions, I had to tweak the simplification machinery to accept
those unspecs, and to add some means for output_addr_const() to
call-back into machine-specific code.
Here's the resulting patch. No regressions on sh-elf, with and
without -fPIC, and hundreds of fixes on sh-hms. Ok to install?
Index: gcc/ChangeLog
from Alexandre Oliva <aoliva@redhat.com>
* final.c (output_addr_const) [LABEL_REF]: Simplify.
[MINUS]: Enclose non-CONST_INTs in parentheses.
[default]: Try OUTPUT_ADDR_CONST_EXTRA.
* tm.texi (OUTPUT_ADDR_CONST_EXTRA): Document it.
* varasm.c (decode_rtx_const) [CONST]: If it's not something
PLUS or MINUS a CONST_INT, use the whole CONST with offset 0
instead of abort()ing.
* sh.c (output_pic_addr_const): Removed. Fixed all callers.
* sh.h (OUTPUT_ADDR_CONST_EXTRA): New. Handle the UNSPECs
formerly handled in output_pic_addr_const.
* sh.md (sym_label2reg, symPLT_label2reg): Enclose UNSPEC
operands of MINUS in CONSTs so that decode_rtx_const() will
accept them.
Index: gcc/final.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/final.c,v
retrieving revision 1.147
diff -u -p -r1.147 final.c
--- gcc/final.c 2000/11/08 02:18:00 1.147
+++ gcc/final.c 2000/11/08 04:07:31
@@ -3677,10 +3677,8 @@ output_addr_const (file, x)
break;
case LABEL_REF:
- ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (XEXP (x, 0)));
- assemble_name (file, buf);
- break;
-
+ x = XEXP (x, 0);
+ /* Fall through. */
case CODE_LABEL:
ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
assemble_name (file, buf);
@@ -3741,8 +3739,9 @@ output_addr_const (file, x)
output_addr_const (file, XEXP (x, 0));
fprintf (file, "-");
- if (GET_CODE (XEXP (x, 1)) == CONST_INT
- && INTVAL (XEXP (x, 1)) < 0)
+ if ((GET_CODE (XEXP (x, 1)) == CONST_INT
+ && INTVAL (XEXP (x, 1)) < 0)
+ || GET_CODE (XEXP (x, 1)) != CONST_INT)
{
fprintf (file, "%s", ASM_OPEN_PAREN);
output_addr_const (file, XEXP (x, 1));
@@ -3758,6 +3757,12 @@ output_addr_const (file, x)
break;
default:
+#ifdef OUTPUT_ADDR_CONST_EXTRA
+ OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
+ break;
+
+ fail:
+#endif
output_operand_lossage ("invalid expression as operand");
}
}
Index: gcc/tm.texi
===================================================================
RCS file: /cvs/gcc/egcs/gcc/tm.texi,v
retrieving revision 1.150
diff -u -p -r1.150 tm.texi
--- gcc/tm.texi 2000/11/01 00:20:34 1.150
+++ gcc/tm.texi 2000/11/08 04:07:37
@@ -5500,6 +5500,18 @@ would be identical to repeatedly calling
a size of @code{UNITS_PER_WORD}, once for each word, you need not define
the macro.
+@findex OUTPUT_ADDR_CONST_EXTRA
+@item OUTPUT_ADDR_CONST_EXTRA (@var{stream}, @var{x}, @var{fail})
+A C statement to recognize @var{rtx} patterns that
+@code{output_addr_const} can't deal with, and output assembly code to
+@var{stream} corresponding to the pattern @var{x}. This may be used to
+allow machine-dependent @code{UNSPEC}s to appear within constants.
+
+If @code{OUTPUT_ADDR_CONST_EXTRA} fails to recognize a pattern, it must
+@code{goto fail}, so that a standard error message is printed. If it
+prints an error message itself, by calling, for example,
+@code{output_operand_lossage}, it may just complete normally.
+
@findex ASM_OUTPUT_BYTE
@item ASM_OUTPUT_BYTE (@var{stream}, @var{value})
A C statement to output to the stdio stream @var{stream} an assembler
Index: gcc/varasm.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/varasm.c,v
retrieving revision 1.137
diff -u -p -r1.137 varasm.c
--- gcc/varasm.c 2000/11/03 18:55:53 1.137
+++ gcc/varasm.c 2000/11/08 04:07:39
@@ -3386,22 +3386,21 @@ decode_rtx_const (mode, x, value)
case CONST:
x = XEXP (x, 0);
- if (GET_CODE (x) == PLUS)
+ if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT)
{
value->un.addr.base = XEXP (x, 0);
- if (GET_CODE (XEXP (x, 1)) != CONST_INT)
- abort ();
value->un.addr.offset = INTVAL (XEXP (x, 1));
}
- else if (GET_CODE (x) == MINUS)
+ else if (GET_CODE (x) == MINUS && GET_CODE (XEXP (x, 1)) == CONST_INT)
{
value->un.addr.base = XEXP (x, 0);
- if (GET_CODE (XEXP (x, 1)) != CONST_INT)
- abort ();
value->un.addr.offset = - INTVAL (XEXP (x, 1));
}
else
- abort ();
+ {
+ value->un.addr.base = x;
+ value->un.addr.offset = 0;
+ }
break;
default:
Index: gcc/config/sh/sh.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/sh/sh.c,v
retrieving revision 1.69
diff -u -p -r1.69 sh.c
--- gcc/config/sh/sh.c 2000/10/31 15:34:27 1.69
+++ gcc/config/sh/sh.c 2000/11/08 04:07:41
@@ -202,7 +202,7 @@ print_operand_address (stream, x)
break;
default:
- output_pic_addr_const (stream, x);
+ output_addr_const (stream, x);
break;
}
}
@@ -5350,120 +5350,4 @@ legitimize_pic_address (orig, mode, reg)
return reg;
}
return orig;
-}
-
-/* Like output_addr_const(), but recognize PIC unspecs and special
- expressions. */
-void
-output_pic_addr_const (file, x)
- FILE *file;
- rtx x;
-{
- char buf[256];
-
- switch (GET_CODE (x))
- {
- case PC:
- if (flag_pic)
- putc ('.', file);
- else
- abort ();
- break;
-
- case SYMBOL_REF:
- assemble_name (file, XSTR (x, 0));
- break;
-
- case LABEL_REF:
- x = XEXP (x, 0);
- /* FALLTHRU */
- case CODE_LABEL:
- ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
- assemble_name (asm_out_file, buf);
- break;
-
- case CONST:
- output_pic_addr_const (file, XEXP (x, 0));
- break;
-
- case CONST_INT:
- fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
- break;
-
- case CONST_DOUBLE:
- if (GET_MODE (x) == VOIDmode)
- {
- /* We can use %d if the number is <32 bits and positive. */
- if (CONST_DOUBLE_HIGH (x) || CONST_DOUBLE_LOW (x) < 0)
- fprintf (file, "0x%lx%08lx",
- (unsigned long) CONST_DOUBLE_HIGH (x),
- (unsigned long) CONST_DOUBLE_LOW (x));
- else
- fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x));
- }
- else
- /* We can't handle floating point constants;
- PRINT_OPERAND must handle them. */
- output_operand_lossage ("floating constant misused");
- break;
-
- case PLUS:
- /* Some assemblers need integer constants to appear first. */
- if (GET_CODE (XEXP (x, 0)) == CONST_INT)
- {
- output_pic_addr_const (file, XEXP (x, 0));
- fprintf (file, "+");
- output_pic_addr_const (file, XEXP (x, 1));
- }
- else if (GET_CODE (XEXP (x, 1)) == CONST_INT
- || GET_CODE (XEXP (x, 0)) == PC)
- {
- output_pic_addr_const (file, XEXP (x, 1));
- fprintf (file, "+");
- output_pic_addr_const (file, XEXP (x, 0));
- }
- else
- abort ();
- break;
-
- case MINUS:
- output_pic_addr_const (file, XEXP (x, 0));
- fprintf (file, "-");
- if (GET_CODE (XEXP (x, 1)) == CONST)
- {
- putc ('(', file);
- output_pic_addr_const (file, XEXP (x, 1));
- putc (')', file);
- }
- else
- output_pic_addr_const (file, XEXP (x, 1));
- break;
-
- case UNSPEC:
- if ((XVECLEN (x, 0)) > 3)
- abort ();
- output_pic_addr_const (file, XVECEXP (x, 0, 0));
- switch (XINT (x, 1))
- {
- case 6:
- /* GLOBAL_OFFSET_TABLE or local symbols, no suffix. */
- break;
- case 7:
- fputs ("@GOT", file);
- break;
- case 8:
- fputs ("@GOTOFF", file);
- break;
- case 9:
- fputs ("@PLT", file);
- break;
- default:
- output_operand_lossage ("invalid UNSPEC as operand");
- break;
- }
- break;
-
- default:
- output_operand_lossage ("invalid expression as operand");
- }
}
Index: gcc/config/sh/sh.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/sh/sh.h,v
retrieving revision 1.81
diff -u -p -r1.81 sh.h
--- gcc/config/sh/sh.h 2000/11/02 23:29:13 1.81
+++ gcc/config/sh/sh.h 2000/11/08 04:07:42
@@ -2069,12 +2069,12 @@ do { char dstr[30]; \
#define ASM_OUTPUT_INT(STREAM, EXP) \
(fprintf ((STREAM), "\t.long\t"), \
- output_pic_addr_const ((STREAM), (EXP)), \
+ output_addr_const ((STREAM), (EXP)), \
fputc ('\n', (STREAM)))
#define ASM_OUTPUT_SHORT(STREAM, EXP) \
(fprintf ((STREAM), "\t.short\t"), \
- output_pic_addr_const ((STREAM), (EXP)), \
+ output_addr_const ((STREAM), (EXP)), \
fputc ('\n', (STREAM)))
#define ASM_OUTPUT_CHAR(STREAM, EXP) \
@@ -2154,6 +2154,37 @@ do { char dstr[30]; \
#define PRINT_OPERAND_PUNCT_VALID_P(CHAR) \
((CHAR) == '.' || (CHAR) == '#' || (CHAR) == '@' || (CHAR) == ',' \
|| (CHAR) == '$')
+
+/* Recognize machine-specific patterns that may appear within
+ constants. Used for PIC-specific UNSPECs. */
+#define OUTPUT_ADDR_CONST_EXTRA(STREAM, X, FAIL) \
+ do \
+ if (flag_pic && GET_CODE (X) == UNSPEC && XVECLEN ((X), 0) == 1) \
+ { \
+ output_addr_const ((STREAM), XVECEXP ((X), 0, 0)); \
+ switch (XINT ((X), 1)) \
+ { \
+ case 6: \
+ /* GLOBAL_OFFSET_TABLE or local symbols, no suffix. */ \
+ break; \
+ case 7: \
+ fputs ("@GOT", (STREAM)); \
+ break; \
+ case 8: \
+ fputs ("@GOTOFF", (STREAM)); \
+ break; \
+ case 9: \
+ fputs ("@PLT", (STREAM)); \
+ break; \
+ default: \
+ goto FAIL; \
+ } \
+ break; \
+ } \
+ else \
+ goto FAIL; \
+ while (0)
+
extern struct rtx_def *sh_compare_op0;
extern struct rtx_def *sh_compare_op1;
Index: gcc/config/sh/sh.md
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/sh/sh.md,v
retrieving revision 1.54
diff -u -p -r1.54 sh.md
--- gcc/config/sh/sh.md 2000/10/31 15:34:27 1.54
+++ gcc/config/sh/sh.md 2000/11/08 04:07:43
@@ -3485,7 +3485,7 @@
(define_expand "sym_label2reg"
[(set (match_operand:SI 0 "" "")
(const (minus:SI
- (unspec [(match_operand:SI 1 "" "")] 6)
+ (const (unspec [(match_operand:SI 1 "" "")] 6))
(const (plus:SI
(unspec [(label_ref (match_operand:SI 2 "" ""))] 6)
(const_int 2))))))]
@@ -3517,12 +3517,11 @@
(define_expand "symPLT_label2reg"
[(set (match_operand:SI 0 "" "")
(const (minus:SI
- (plus:SI (pc)
- (unspec [(match_operand:SI 1 "" "")] 9))
- (const
- (plus:SI
- (unspec [(label_ref (match_operand:SI 2 "" ""))] 6)
- (const_int 2))))))
+ (const (plus:SI (unspec [(match_operand:SI 1 "" "")] 9)
+ (pc)))
+ (const (plus:SI
+ (unspec [(label_ref (match_operand:SI 2 "" ""))] 6)
+ (const_int 2))))))
(use (match_dup 3))]
;; Even though the PIC register is not really used by the call
;; sequence in which this is expanded, the PLT code assumes the PIC
--
Alexandre Oliva Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist *Please* write to mailing lists, not to me