From f961ec70ee07768f87e9e2ce2b3cac4160fd065e Mon Sep 17 00:00:00 2001 From: Andrew Stubbs Date: Fri, 14 Dec 2018 11:49:28 +0000 Subject: 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 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 --- gcc/lra.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'gcc/lra.c') diff --git a/gcc/lra.c b/gcc/lra.c index 537b4ae..ae82b60 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) -- cgit v1.1