diff options
Diffstat (limited to 'gcc/genrecog.c')
| -rw-r--r-- | gcc/genrecog.c | 218 |
1 files changed, 0 insertions, 218 deletions
diff --git a/gcc/genrecog.c b/gcc/genrecog.c index 74dd0a7..824cf75 100644 --- a/gcc/genrecog.c +++ b/gcc/genrecog.c @@ -171,219 +171,6 @@ static int max_depth; /* The line number of the start of the pattern currently being processed. */ static int pattern_lineno; -/* Predicate handling. - - We construct from the machine description a table mapping each - predicate to a list of the rtl codes it can possibly match. The - function 'maybe_both_true' uses it to deduce that there are no - expressions that can be matches by certain pairs of tree nodes. - Also, if a predicate can match only one code, we can hardwire that - code into the node testing the predicate. - - Some predicates are flagged as special. validate_pattern will not - warn about modeless match_operand expressions if they have a - special predicate. Predicates that allow only constants are also - treated as special, for this purpose. - - validate_pattern will warn about predicates that allow non-lvalues - when they appear in destination operands. - - Calculating the set of rtx codes that can possibly be accepted by a - predicate expression EXP requires a three-state logic: any given - subexpression may definitively accept a code C (Y), definitively - reject a code C (N), or may have an indeterminate effect (I). N - and I is N; Y or I is Y; Y and I, N or I are both I. Here are full - truth tables. - - a b a&b a|b - Y Y Y Y - N Y N Y - N N N N - I Y I Y - I N N I - I I I I - - We represent Y with 1, N with 0, I with 2. If any code is left in - an I state by the complete expression, we must assume that that - code can be accepted. */ - -#define N 0 -#define Y 1 -#define I 2 - -#define TRISTATE_AND(a,b) \ - ((a) == I ? ((b) == N ? N : I) : \ - (b) == I ? ((a) == N ? N : I) : \ - (a) && (b)) - -#define TRISTATE_OR(a,b) \ - ((a) == I ? ((b) == Y ? Y : I) : \ - (b) == I ? ((a) == Y ? Y : I) : \ - (a) || (b)) - -#define TRISTATE_NOT(a) \ - ((a) == I ? I : !(a)) - -/* 0 means no warning about that code yet, 1 means warned. */ -static char did_you_mean_codes[NUM_RTX_CODE]; - -/* Recursively calculate the set of rtx codes accepted by the - predicate expression EXP, writing the result to CODES. */ -static void -compute_predicate_codes (rtx exp, char codes[NUM_RTX_CODE]) -{ - char op0_codes[NUM_RTX_CODE]; - char op1_codes[NUM_RTX_CODE]; - char op2_codes[NUM_RTX_CODE]; - int i; - - switch (GET_CODE (exp)) - { - case AND: - compute_predicate_codes (XEXP (exp, 0), op0_codes); - compute_predicate_codes (XEXP (exp, 1), op1_codes); - for (i = 0; i < NUM_RTX_CODE; i++) - codes[i] = TRISTATE_AND (op0_codes[i], op1_codes[i]); - break; - - case IOR: - compute_predicate_codes (XEXP (exp, 0), op0_codes); - compute_predicate_codes (XEXP (exp, 1), op1_codes); - for (i = 0; i < NUM_RTX_CODE; i++) - codes[i] = TRISTATE_OR (op0_codes[i], op1_codes[i]); - break; - case NOT: - compute_predicate_codes (XEXP (exp, 0), op0_codes); - for (i = 0; i < NUM_RTX_CODE; i++) - codes[i] = TRISTATE_NOT (op0_codes[i]); - break; - - case IF_THEN_ELSE: - /* a ? b : c accepts the same codes as (a & b) | (!a & c). */ - compute_predicate_codes (XEXP (exp, 0), op0_codes); - compute_predicate_codes (XEXP (exp, 1), op1_codes); - compute_predicate_codes (XEXP (exp, 2), op2_codes); - for (i = 0; i < NUM_RTX_CODE; i++) - codes[i] = TRISTATE_OR (TRISTATE_AND (op0_codes[i], op1_codes[i]), - TRISTATE_AND (TRISTATE_NOT (op0_codes[i]), - op2_codes[i])); - break; - - case MATCH_CODE: - /* MATCH_CODE allows a specified list of codes. However, if it - does not apply to the top level of the expression, it does not - constrain the set of codes for the top level. */ - if (XSTR (exp, 1)[0] != '\0') - { - memset (codes, Y, NUM_RTX_CODE); - break; - } - - memset (codes, N, NUM_RTX_CODE); - { - const char *next_code = XSTR (exp, 0); - const char *code; - - if (*next_code == '\0') - { - error_with_line (pattern_lineno, "empty match_code expression"); - break; - } - - while ((code = scan_comma_elt (&next_code)) != 0) - { - size_t n = next_code - code; - int found_it = 0; - - for (i = 0; i < NUM_RTX_CODE; i++) - if (!strncmp (code, GET_RTX_NAME (i), n) - && GET_RTX_NAME (i)[n] == '\0') - { - codes[i] = Y; - found_it = 1; - break; - } - if (!found_it) - { - error_with_line (pattern_lineno, - "match_code \"%.*s\" matches nothing", - (int) n, code); - for (i = 0; i < NUM_RTX_CODE; i++) - if (!strncasecmp (code, GET_RTX_NAME (i), n) - && GET_RTX_NAME (i)[n] == '\0' - && !did_you_mean_codes[i]) - { - did_you_mean_codes[i] = 1; - message_with_line (pattern_lineno, "(did you mean \"%s\"?)", GET_RTX_NAME (i)); - } - } - - } - } - break; - - case MATCH_OPERAND: - /* MATCH_OPERAND disallows the set of codes that the named predicate - disallows, and is indeterminate for the codes that it does allow. */ - { - struct pred_data *p = lookup_predicate (XSTR (exp, 1)); - if (!p) - { - error_with_line (pattern_lineno, - "reference to unknown predicate '%s'", - XSTR (exp, 1)); - break; - } - for (i = 0; i < NUM_RTX_CODE; i++) - codes[i] = p->codes[i] ? I : N; - } - break; - - - case MATCH_TEST: - /* (match_test WHATEVER) is completely indeterminate. */ - memset (codes, I, NUM_RTX_CODE); - break; - - default: - error_with_line (pattern_lineno, - "'%s' cannot be used in a define_predicate expression", - GET_RTX_NAME (GET_CODE (exp))); - memset (codes, I, NUM_RTX_CODE); - break; - } -} - -#undef TRISTATE_OR -#undef TRISTATE_AND -#undef TRISTATE_NOT - -/* Process a define_predicate expression: compute the set of predicates - that can be matched, and record this as a known predicate. */ -static void -process_define_predicate (rtx desc) -{ - struct pred_data *pred = XCNEW (struct pred_data); - char codes[NUM_RTX_CODE]; - int i; - - pred->name = XSTR (desc, 0); - if (GET_CODE (desc) == DEFINE_SPECIAL_PREDICATE) - pred->special = 1; - - compute_predicate_codes (XEXP (desc, 1), codes); - - for (i = 0; i < NUM_RTX_CODE; i++) - if (codes[i] != N) - add_predicate_code (pred, (enum rtx_code) i); - - add_predicate (pred); -} -#undef I -#undef N -#undef Y - - static struct decision *new_decision (const char *, struct decision_head *); static struct decision_test *new_decision_test @@ -2716,11 +2503,6 @@ main (int argc, char **argv) switch (GET_CODE (desc)) { - case DEFINE_PREDICATE: - case DEFINE_SPECIAL_PREDICATE: - process_define_predicate (desc); - break; - case DEFINE_INSN: h = make_insn_sequence (desc, RECOG); merge_trees (&recog_tree, &h); |