[This is new patch not included in the previously posted patch sets.]
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.
2018-12-12 Andrew Stubbs <a...@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.
---
gcc/lra-int.h | 2 +-
gcc/lra-remat.c | 2 +-
gcc/lra.c | 12 ++++++++++--
3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/gcc/lra-int.h b/gcc/lra-int.h
index 5267b53..d5ff652 100644
--- a/gcc/lra-int.h
+++ b/gcc/lra-int.h
@@ -335,7 +335,7 @@ 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;
diff --git a/gcc/lra-remat.c b/gcc/lra-remat.c
index faf74ca..627a248 100644
--- a/gcc/lra-remat.c
+++ b/gcc/lra-remat.c
@@ -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);
}
}
diff --git a/gcc/lra.c b/gcc/lra.c
index 5d58d90..14974ed 100644
--- a/gcc/lra.c
+++ b/gcc/lra.c
@@ -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)
