From 259c3965b1ba04f7ee022846af6173fb1c343bc8 Mon Sep 17 00:00:00 2001 From: Jozef Lawrynowicz Date: Wed, 22 Jul 2020 12:37:29 +0100 Subject: [PATCH] expmed: Fix possible use of NULL_RTX return value from emit_store_flag MSP430 does not support have any store-flag instructions, so emit_store_flag can return NULL_RTX. Catch the NULL_RTX in expmed.c:expand_sdiv_pow2. gcc/ChangeLog: * expmed.c (expand_sdiv_pow2): Check return value from emit_store_flag is not NULL_RTX before use. --- gcc/expmed.c | 35 +++++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/gcc/expmed.c b/gcc/expmed.c index e7c03fbf92c..3d2d2347d79 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -4086,9 +4086,12 @@ expand_sdiv_pow2 (scalar_int_mode mode, rtx op0, HOST_WIDE_INT d) { temp = gen_reg_rtx (mode); temp = emit_store_flag (temp, LT, op0, const0_rtx, mode, 0, 1); - temp = expand_binop (mode, add_optab, temp, op0, NULL_RTX, - 0, OPTAB_LIB_WIDEN); - return expand_shift (RSHIFT_EXPR, mode, temp, logd, NULL_RTX, 0); + if (temp != NULL_RTX) + { + temp = expand_binop (mode, add_optab, temp, op0, NULL_RTX, + 0, OPTAB_LIB_WIDEN); + return expand_shift (RSHIFT_EXPR, mode, temp, logd, NULL_RTX, 0); + } } if (HAVE_conditional_move @@ -4122,17 +4125,21 @@ expand_sdiv_pow2 (scalar_int_mode mode, rtx op0, HOST_WIDE_INT d) temp = gen_reg_rtx (mode); temp = emit_store_flag (temp, LT, op0, const0_rtx, mode, 0, -1); - if (GET_MODE_BITSIZE (mode) >= BITS_PER_WORD - || shift_cost (optimize_insn_for_speed_p (), mode, ushift) - > COSTS_N_INSNS (1)) - temp = expand_binop (mode, and_optab, temp, gen_int_mode (d - 1, mode), - NULL_RTX, 0, OPTAB_LIB_WIDEN); - else - temp = expand_shift (RSHIFT_EXPR, mode, temp, - ushift, NULL_RTX, 1); - temp = expand_binop (mode, add_optab, temp, op0, NULL_RTX, - 0, OPTAB_LIB_WIDEN); - return expand_shift (RSHIFT_EXPR, mode, temp, logd, NULL_RTX, 0); + if (temp != NULL_RTX) + { + if (GET_MODE_BITSIZE (mode) >= BITS_PER_WORD + || shift_cost (optimize_insn_for_speed_p (), mode, ushift) + > COSTS_N_INSNS (1)) + temp = expand_binop (mode, and_optab, temp, + gen_int_mode (d - 1, mode), + NULL_RTX, 0, OPTAB_LIB_WIDEN); + else + temp = expand_shift (RSHIFT_EXPR, mode, temp, + ushift, NULL_RTX, 1); + temp = expand_binop (mode, add_optab, temp, op0, NULL_RTX, + 0, OPTAB_LIB_WIDEN); + return expand_shift (RSHIFT_EXPR, mode, temp, logd, NULL_RTX, 0); + } } label = gen_label_rtx (); -- 2.30.2