diff options
| -rw-r--r-- | simplify.c | 24 | ||||
| -rw-r--r-- | validation/optim/mask-lsr.c | 1 |
2 files changed, 24 insertions, 1 deletions
@@ -575,12 +575,25 @@ static long long check_shift_count(struct instruction *insn, unsigned long long return sval; } +static int simplify_or_lsr(struct instruction *insn, pseudo_t src, pseudo_t other, unsigned shift) +{ + // src->def->opcode == OP_AND + pseudo_t src2 = src->def->src2; + + if (!constant(src2)) + return 0; + if (((unsigned long long) src2->value) >> shift) + return 0; + return replace_pseudo(insn, &insn->src1, other); +} + static int simplify_shift(struct instruction *insn, pseudo_t pseudo, long long value) { struct instruction *def; unsigned long long nval; unsigned int size; pseudo_t src2; + pseudo_t src; if (!value) return replace_with_pseudo(insn, pseudo); @@ -632,6 +645,17 @@ static int simplify_shift(struct instruction *insn, pseudo_t pseudo, long long v switch(DEF_OPCODE(def, pseudo)) { case OP_LSR: goto case_shift_shift; + case OP_OR: + // replace ((A & M) | B) >> S + // by (B >> S) + // when (M >> S) == 0 + src = def->src1; + if (def_opcode(src) == OP_AND) + return simplify_or_lsr(insn, src, def->src2, value); + src = def->src2; + if (def_opcode(src) == OP_AND) + return simplify_or_lsr(insn, src, def->src1, value); + break; } break; case OP_SHL: diff --git a/validation/optim/mask-lsr.c b/validation/optim/mask-lsr.c index 1d37c91e..ec636444 100644 --- a/validation/optim/mask-lsr.c +++ b/validation/optim/mask-lsr.c @@ -8,7 +8,6 @@ unsigned int foo(unsigned int x, unsigned int y) /* * check-name: mask-lsr * check-command: test-linearize -Wno-decl $file - * check-known-to-fail * * check-output-ignore * check-output-excludes: %arg1 |