diff options
Diffstat (limited to 'simplify.c')
| -rw-r--r-- | simplify.c | 98 |
1 files changed, 98 insertions, 0 deletions
@@ -1258,6 +1258,104 @@ static int simplify_compare_constant(struct instruction *insn, long long value) src2 = insn->src2; value = src2->value; switch (DEF_OPCODE(def, src1)) { + case OP_AND: + if (!constant(def->src2)) + break; + bits = def->src2->value; + switch (insn->opcode) { + case OP_SET_EQ: + if ((value & bits) != value) + return replace_with_value(insn, 0); + break; + case OP_SET_NE: + if ((value & bits) != value) + return replace_with_value(insn, 1); + break; + case OP_SET_LE: + value = sign_extend(value, def->size); + if (bits & sign_bit(def->size)) + break; + if (value < 0) + return replace_with_value(insn, 0); + if (value >= (long long)bits) + return replace_with_value(insn, 1); + if (value == 0) + return replace_opcode(insn, OP_SET_EQ); + break; + case OP_SET_GT: + value = sign_extend(value, def->size); + if (bits & sign_bit(def->size)) + break; + if (value < 0) + return replace_with_value(insn, 1); + if (value >= (long long)bits) + return replace_with_value(insn, 0); + if (value == 0) + return replace_opcode(insn, OP_SET_NE); + break; + case OP_SET_B: + if (value > bits) + return replace_with_value(insn, 1); + break; + case OP_SET_BE: + if (value >= bits) + return replace_with_value(insn, 1); + break; + case OP_SET_AE: + if (value > bits) + return replace_with_value(insn, 0); + break; + case OP_SET_A: + if (value >= bits) + return replace_with_value(insn, 0); + break; + } + break; + case OP_OR: + if (!constant(def->src2)) + break; + bits = def->src2->value; + switch (insn->opcode) { + case OP_SET_EQ: + if ((value & bits) != bits) + return replace_with_value(insn, 0); + break; + case OP_SET_NE: + if ((value & bits) != bits) + return replace_with_value(insn, 1); + break; + case OP_SET_B: + if (bits >= value) + return replace_with_value(insn, 0); + break; + case OP_SET_BE: + if (bits > value) + return replace_with_value(insn, 0); + break; + case OP_SET_AE: + if (bits > value) + return replace_with_value(insn, 1); + break; + case OP_SET_A: + if (bits >= value) + return replace_with_value(insn, 1); + break; + case OP_SET_LE: + value = sign_extend(value, def->size); + if (bits & sign_bit(def->size)) { + if (value >= -1) + return replace_with_value(insn, 1); + } + break; + case OP_SET_GT: + value = sign_extend(value, def->size); + if (bits & sign_bit(def->size)) { + if (value >= -1) + return replace_with_value(insn, 0); + } + break; + } + break; case OP_SEXT: // sext(x) cmp C --> x cmp trunc(C) osize = def->orig_type->bit_size; if (is_signed_constant(value, osize, size)) { |