scc

Simple C99 Compiler
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commit a63b11584c3d43ddcc2080dca8ce692aa56c3d52
parent 624848780072de338c258596833708934bed9204
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Thu,  7 Jan 2016 16:52:45 +0100

Implement type rules in ternary operator

The rules of ths standard about the types implied
in the ternary operator are complex, and I was not
matching them. This patch breaks the test003,
because optimization of ternary is removed.

Diffstat:
cc1/expr.c | 125+++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------------
1 file changed, 87 insertions(+), 38 deletions(-)

diff --git a/cc1/expr.c b/cc1/expr.c @@ -79,27 +79,98 @@ promote(Node *np) } static void -typeconv(Node **p1, Node **p2) +arithconv(Node **p1, Node **p2) { + int n, to = 0, s1, s2; + unsigned r1, r2; Type *tp1, *tp2; Node *np1, *np2; - int n; + struct limits *lp1, *lp2; np1 = promote(*p1); np2 = promote(*p2); tp1 = np1->type; tp2 = np2->type; - if (tp1 != tp2) { - if ((n = tp1->n.rank - tp2->n.rank) > 0) - np2 = convert(np2, tp1, 1); - else if (n < 0) - np1 = convert(np1, tp2, 1); + + if (tp1 == tp2) + goto set_p1_p2; + + s1 = tp1->sign, r1 = tp1->n.rank, lp1 = getlimits(tp1); + s2 = tp2->sign, r2 = tp2->n.rank, lp2 = getlimits(tp2); + + if (s1 == s2 || tp1->op == FLOAT || tp2->op == FLOAT) { + to = r1 - r2; + } else if (!s1) { + if (r1 >= r2 || lp1->max.i >= lp2->max.i) + to = 1; + else + to = -1; + } else { + if (r2 >= r1 || lp2->max.i >= lp1->max.i) + to = -1; + else + to = 1; } + + if (to > 0) + np2 = convert(np2, tp1, 1); + else if (to < 0) + np1 = convert(np1, tp2, 1); + +set_p1_p2: *p1 = np1; *p2 = np2; } +static Node * +chkternary(Node *ifyes, Node *ifno) +{ + int arithy = 0, aithn = 0; + Type *tyes, *tno; + + tyes = ifyes->type, tno = ifno->type; + + switch (tyes->op) { + case ENUM: + case INT: + case FLOAT: + switch (tno->op) { + case ENUM: + case INT: + case FLOAT: + arithconv(&ifyes, &ifno); + break; + default: + goto wrong_type; + } + break; + case ARY: + case FTN: + ifyes = decay(ifyes); + tyes = ifyes->type; + ifno = decay(ifno); + tno = ifno->type; + case PTR: + if ((ifno = convert(ifno, tyes, 0)) == NULL) + goto wrong_type; + break; + case VOID: + case STRUCT: + case UNION: + if (!eqtype(tyes, tno)) + goto wrong_type; + break; + default: + abort(); + } + return node(OCOLON, ifyes->type, ifyes, ifno); + +wrong_type: + errorp("type mismatch in conditional expression"); + return node(OCOLON, ifyes->type, ifyes, ifyes); +} + static void chklvalue(Node *np) { @@ -135,7 +206,7 @@ integerop(char op, Node *lp, Node *rp) { if (BTYPE(lp) != INT || BTYPE(rp) != INT) error("operator requires integer operands"); - typeconv(&lp, &rp); + arithconv(&lp, &rp); return simplify(op, lp->type, lp, rp); } @@ -181,7 +252,7 @@ convert(Node *np, Type *newtp, char iscast) case FLOAT: switch (newtp->op) { case PTR: - if (!iscast || oldtp->op == FLOAT) + if (oldtp->op == FLOAT || !cmpnode(np, 0) && !iscast) return NULL; /* PASSTHROUGH */ case INT: @@ -203,8 +274,7 @@ convert(Node *np, Type *newtp, char iscast) break; case PTR: if (iscast || - newtp == pvoidtype || - oldtp == pvoidtype) { + newtp == pvoidtype || oldtp == pvoidtype) { /* TODO: * we assume conversion between pointers * do not need any operation, but due to @@ -260,7 +330,7 @@ arithmetic(char op, Node *lp, Node *rp) switch (BTYPE(rp)) { case INT: case FLOAT: - typeconv(&lp, &rp); + arithconv(&lp, &rp); break; case PTR: if (op == OADD || op == OSUB) @@ -309,7 +379,7 @@ compare(char op, Node *lp, Node *rp) switch (BTYPE(rp)) { case INT: case FLOAT: - typeconv(&lp, &rp); + arithconv(&lp, &rp); break; case PTR: return pcompare(op, rp, lp); @@ -436,15 +506,7 @@ array(Node *lp, Node *rp) static Node * assignop(char op, Node *lp, Node *rp) { - int force = 0; - Type *tp = lp->type; - - rp = decay(rp); - if (BTYPE(rp) == INT && tp->op == PTR && cmpnode(rp, 0)) { - tp = pvoidtype; - force = 1; - } - if ((rp = convert(rp, tp, force)) == NULL) { + if ((rp = convert(decay(rp), lp->type, 0)) == NULL) { errorp((op == OINIT) ? "incorrect initiliazer" : "incompatible types when assigning"); @@ -937,23 +999,10 @@ ternary(void) Node *ifyes, *ifno, *np; cond = exp2cond(cond, 0); - ifyes = promote(expr()); + ifyes = expr(); expect(':'); - ifno = promote(ternary()); - typeconv(&ifyes, &ifno); - if (cond->constant) { - TINT i = cond->sym->u.i; - - freetree(cond); - if (i == 0) { - freetree(ifyes); - return ifno; - } else { - freetree(ifno); - return ifyes; - } - } - np = node(OCOLON, ifyes->type, ifyes, ifno); + ifno = ternary(); + np = chkternary(ifyes, ifno); cond = node(OASK, np->type, cond, np); } return cond;