git
/
gcc
mirror of git://gcc.gnu.org/git/gcc.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix LRA bug 

This patch fixes an ICE building libgfortran/random.c.

The problem was an adddi3 instruction that had an eliminable frame pointer.
GCN adddi3 includes a match_scratch, which LRA substitutes with a REG, and
checks if it can be converted back to a scratch afterwards.  In the meantime,
the add was converted to a move, meaning that the instruction pattern
completely changed, thus causing a segfault when the instruction is revisited
in restore_scratches.

2018-12-14  Andrew Stubbs  <ams@codesourcery.com>

	gcc/
	* gcc/lra-int.h (lra_register_new_scratch_op): Add third parameter.
	* gcc/lra-remat.c (update_scratch_ops): Pass icode to
	lra_register_new_scratch_op.
	* gcc/lra.c (struct sloc): Add icode field.
	(lra_register_new_scratch_op): Add icode parameter.
	Use icode to skip insns that have changed beyond recognition.

From-SVN: r267132
This commit is contained in:
Andrew Stubbs 2018-12-14 11:49:28 +00:00 committed by Andrew Stubbs
parent 65e0a92b23
commit f961ec70ee
4 changed files with 21 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
gcc/ChangeLog
View File

@ -1,3 +1,12 @@
2018-12-14 Andrew Stubbs <ams@codesourcery.com>
* gcc/lra-int.h (lra_register_new_scratch_op): Add third parameter.
* gcc/lra-remat.c (update_scratch_ops): Pass icode to
lra_register_new_scratch_op.
* gcc/lra.c (struct sloc): Add icode field.
(lra_register_new_scratch_op): Add icode parameter.
Use icode to skip insns that have changed beyond recognition.
2018-12-14 Eric Botcazou <ebotcazou@adacore.com>
* dwarf2out.c (analyze_discr_in_predicate): Simplify.

2
gcc/lra-int.h
View File

@ -336,7 +336,7 @@ extern void lra_create_copy (int, int, int);
extern lra_copy_t lra_get_copy (int);
extern bool lra_former_scratch_p (int);
extern bool lra_former_scratch_operand_p (rtx_insn *, int);
extern void lra_register_new_scratch_op (rtx_insn *, int);
extern void lra_register_new_scratch_op (rtx_insn *, int, int);
extern int lra_new_regno_start;
extern int lra_constraint_new_regno_start;

2
gcc/lra-remat.c
View File

@ -1042,7 +1042,7 @@ update_scratch_ops (rtx_insn *remat_insn)
fprintf (lra_dump_file, " Assigning the same %d to r%d\n",
REGNO (*loc), hard_regno);
}
lra_register_new_scratch_op (remat_insn, i);
lra_register_new_scratch_op (remat_insn, i, id->icode);
}
}

12
gcc/lra.c
View File

@ -2026,6 +2026,7 @@ struct sloc
{
rtx_insn *insn; /* Insn where the scratch was. */
int nop; /* Number of the operand which was a scratch. */
int icode; /* Original icode from which scratch was removed. */
};
typedef struct sloc *sloc_t;
@ -2057,7 +2058,7 @@ lra_former_scratch_operand_p (rtx_insn *insn, int nop)
/* Register operand NOP in INSN as a former scratch. It will be
changed to scratch back, if it is necessary, at the LRA end. */
void
lra_register_new_scratch_op (rtx_insn *insn, int nop)
lra_register_new_scratch_op (rtx_insn *insn, int nop, int icode)
{
lra_insn_recog_data_t id = lra_get_insn_recog_data (insn);
rtx op = *id->operand_loc[nop];
@ -2065,6 +2066,7 @@ lra_register_new_scratch_op (rtx_insn *insn, int nop)
lra_assert (REG_P (op));
loc->insn = insn;
loc->nop = nop;
loc->icode = icode;
scratches.safe_push (loc);
bitmap_set_bit (&scratch_bitmap, REGNO (op));
bitmap_set_bit (&scratch_operand_bitmap,
@ -2102,7 +2104,7 @@ remove_scratches (void)
*id->operand_loc[i] = reg
= lra_create_new_reg (static_id->operand[i].mode,
*id->operand_loc[i], ALL_REGS, NULL);
lra_register_new_scratch_op (insn, i);
lra_register_new_scratch_op (insn, i, id->icode);
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
"Removing SCRATCH in insn #%u (nop %d)\n",
@ -2136,6 +2138,12 @@ restore_scratches (void)
last = loc->insn;
id = lra_get_insn_recog_data (last);
}
if (loc->icode != id->icode)
{
/* The icode doesn't match, which means the insn has been modified
(e.g. register elimination). The scratch cannot be restored. */
continue;
}
if (REG_P (*id->operand_loc[loc->nop])
&& ((regno = REGNO (*id->operand_loc[loc->nop]))
>= FIRST_PSEUDO_REGISTER)