diff options
Diffstat (limited to 'src/evaluate.c')
| -rw-r--r-- | src/evaluate.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/src/evaluate.c b/src/evaluate.c index 7444d09c..f862cd04 100644 --- a/src/evaluate.c +++ b/src/evaluate.c @@ -698,6 +698,7 @@ static int constant_binop_simplify(struct eval_ctx *ctx, struct expr **expr) break; case OP_LSHIFT: assert(left->byteorder == BYTEORDER_HOST_ENDIAN); + mpz_set(val, left->value); mpz_lshift_ui(val, mpz_get_uint32(right->value)); mpz_and(val, val, mask); break; @@ -1094,6 +1095,8 @@ static int binop_can_transfer(struct eval_ctx *ctx, return expr_binary_error(ctx->msgs, right, left, "Comparison is always false"); return 1; + case OP_RSHIFT: + return 1; case OP_XOR: return 1; default: @@ -1111,6 +1114,10 @@ static int binop_transfer_one(struct eval_ctx *ctx, (*right) = binop_expr_alloc(&(*right)->location, OP_RSHIFT, *right, expr_get(left->right)); break; + case OP_RSHIFT: + (*right) = binop_expr_alloc(&(*right)->location, OP_LSHIFT, + *right, expr_get(left->right)); + break; case OP_XOR: (*right) = binop_expr_alloc(&(*right)->location, OP_XOR, *right, expr_get(left->right)); @@ -1125,6 +1132,7 @@ static int binop_transfer_one(struct eval_ctx *ctx, static int binop_transfer(struct eval_ctx *ctx, struct expr **expr) { struct expr *left = (*expr)->left, *i, *next; + unsigned int shift; int err; if (left->ops->type != EXPR_BINOP) @@ -1156,10 +1164,24 @@ static int binop_transfer(struct eval_ctx *ctx, struct expr **expr) return 0; } - left = expr_get((*expr)->left->left); - left->dtype = (*expr)->left->dtype; - expr_free((*expr)->left); - (*expr)->left = left; + switch (left->op) { + case OP_RSHIFT: + /* Mask out the bits the shift would have masked out */ + shift = mpz_get_uint8(left->right->value); + mpz_bitmask(left->right->value, left->left->len); + mpz_lshift_ui(left->right->value, shift); + left->op = OP_AND; + break; + case OP_LSHIFT: + case OP_XOR: + left = expr_get((*expr)->left->left); + left->dtype = (*expr)->left->dtype; + expr_free((*expr)->left); + (*expr)->left = left; + break; + default: + BUG("invalid binop operation %u", left->op); + } return 0; } |