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-rw-r--r--mi/fold.c390
1 files changed, 195 insertions, 195 deletions
diff --git a/mi/fold.c b/mi/fold.c
index 2658431..f62e440 100644
--- a/mi/fold.c
+++ b/mi/fold.c
@@ -15,226 +15,226 @@
static int getintlit(Node *n, vlong *v)
{
- Node *l;
-
- if (exprop(n) != Olit)
- return 0;
- l = n->expr.args[0];
- if (l->lit.littype != Lint)
- return 0;
- *v = l->lit.intval;
- return 1;
+ Node *l;
+
+ if (exprop(n) != Olit)
+ return 0;
+ l = n->expr.args[0];
+ if (l->lit.littype != Lint)
+ return 0;
+ *v = l->lit.intval;
+ return 1;
}
static int isintval(Node *n, vlong val)
{
- vlong v;
+ vlong v;
- if (!getintlit(n, &v))
- return 0;
- return v == val;
+ if (!getintlit(n, &v))
+ return 0;
+ return v == val;
}
static Node *val(Srcloc loc, vlong val, Type *t)
{
- Node *l, *n;
+ Node *l, *n;
- l = mkint(loc, val);
- n = mkexpr(loc, Olit, l, NULL);
- l->lit.type = t;
- n->expr.type = t;
- return n;
+ l = mkint(loc, val);
+ n = mkexpr(loc, Olit, l, NULL);
+ l->lit.type = t;
+ n->expr.type = t;
+ return n;
}
static int issmallconst(Node *dcl)
{
- Type *t;
-
- if (!dcl->decl.isconst)
- return 0;
- if (!dcl->decl.init)
- return 0;
- t = tybase(exprtype(dcl->decl.init));
- if (t->type <= Tyflt64)
- return 1;
- return 0;
+ Type *t;
+
+ if (!dcl->decl.isconst)
+ return 0;
+ if (!dcl->decl.init)
+ return 0;
+ t = tybase(exprtype(dcl->decl.init));
+ if (t->type <= Tyflt64)
+ return 1;
+ return 0;
}
static Node *foldcast(Node *n)
{
- Type *to, *from;
- Node *sub;
-
- sub = n->expr.args[0];
- to = exprtype(n);
- from = exprtype(sub);
-
- switch (tybase(to)->type) {
- case Tybool:
- case Tyint8: case Tyint16: case Tyint32: case Tyint64:
- case Tyuint8: case Tyuint16: case Tyuint32: case Tyuint64:
- case Tyint: case Tyuint: case Tychar: case Tybyte:
- case Typtr:
- switch (tybase(from)->type) {
- case Tybool:
- case Tyint8: case Tyint16: case Tyint32: case Tyint64:
- case Tyuint8: case Tyuint16: case Tyuint32: case Tyuint64:
- case Tyint: case Tyuint: case Tychar: case Tybyte:
- case Typtr:
- if (exprop(sub) == Olit || tybase(from)->type == tybase(to)->type) {
- sub->expr.type = to;
- return sub;
- } else {
- return n;
- }
- default:
- return n;
- }
- default:
- return n;
- }
- return n;
+ Type *to, *from;
+ Node *sub;
+
+ sub = n->expr.args[0];
+ to = exprtype(n);
+ from = exprtype(sub);
+
+ switch (tybase(to)->type) {
+ case Tybool:
+ case Tyint8: case Tyint16: case Tyint32: case Tyint64:
+ case Tyuint8: case Tyuint16: case Tyuint32: case Tyuint64:
+ case Tyint: case Tyuint: case Tychar: case Tybyte:
+ case Typtr:
+ switch (tybase(from)->type) {
+ case Tybool:
+ case Tyint8: case Tyint16: case Tyint32: case Tyint64:
+ case Tyuint8: case Tyuint16: case Tyuint32: case Tyuint64:
+ case Tyint: case Tyuint: case Tychar: case Tybyte:
+ case Typtr:
+ if (exprop(sub) == Olit || tybase(from)->type == tybase(to)->type) {
+ sub->expr.type = to;
+ return sub;
+ } else {
+ return n;
+ }
+ default:
+ return n;
+ }
+ default:
+ return n;
+ }
+ return n;
}
int idxcmp(const void *pa, const void *pb)
{
- Node *a, *b;
- vlong av, bv;
-
- a = *(Node **)pa;
- b = *(Node **)pb;
-
- assert(getintlit(a->expr.idx, &av));
- assert(getintlit(b->expr.idx, &bv));
-
- /* don't trust overflow with int64 */
- if (av < bv)
- return -1;
- else if (av == bv)
- return 0;
- else
- return 1;
+ Node *a, *b;
+ vlong av, bv;
+
+ a = *(Node **)pa;
+ b = *(Node **)pb;
+
+ assert(getintlit(a->expr.idx, &av));
+ assert(getintlit(b->expr.idx, &bv));
+
+ /* don't trust overflow with int64 */
+ if (av < bv)
+ return -1;
+ else if (av == bv)
+ return 0;
+ else
+ return 1;
}
Node *fold(Node *n, int foldvar)
{
- Node **args, *r;
- Type *t;
- vlong a, b;
- size_t i;
-
- if (!n)
- return NULL;
- if (n->type != Nexpr)
- return n;
-
- r = NULL;
- args = n->expr.args;
- if (n->expr.idx)
- n->expr.idx = fold(n->expr.idx, foldvar);
- for (i = 0; i < n->expr.nargs; i++)
- args[i] = fold(args[i], foldvar);
- switch (exprop(n)) {
- case Ovar:
- if (foldvar && issmallconst(decls[n->expr.did]))
- r = fold(decls[n->expr.did]->decl.init, foldvar);
- break;
- case Oadd:
- /* x + 0 = 0 */
- if (isintval(args[0], 0))
- r = args[1];
- if (isintval(args[1], 0))
- r = args[0];
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a + b, exprtype(n));
- break;
- case Osub:
- /* x - 0 = 0 */
- if (isintval(args[1], 0))
- r = args[0];
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a - b, exprtype(n));
- break;
- case Omul:
- /* 1 * x = x */
- if (isintval(args[0], 1))
- r = args[1];
- if (isintval(args[1], 1))
- r = args[0];
- /* 0 * x = 0 */
- if (isintval(args[0], 0))
- r = args[0];
- if (isintval(args[1], 0))
- r = args[1];
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a * b, exprtype(n));
- break;
- case Odiv:
- /* x/0 = error */
- if (isintval(args[1], 0))
- fatal(args[1], "division by zero");
- /* x/1 = x */
- if (isintval(args[1], 1))
- r = args[0];
- /* 0/x = 0 */
- if (isintval(args[1], 0))
- r = args[1];
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a / b, exprtype(n));
- break;
- case Omod:
- /* x%1 = x */
- if (isintval(args[1], 0))
- r = args[0];
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a % b, exprtype(n));
- break;
- case Oneg:
- if (getintlit(args[0], &a))
- r = val(n->loc, -a, exprtype(n));
- break;
- case Obsl:
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a << b, exprtype(n));
- break;
- case Obsr:
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a >> b, exprtype(n));
- break;
- case Obor:
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a | b, exprtype(n));
- break;
- case Oband:
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a & b, exprtype(n));
- break;
- case Obxor:
- if (getintlit(args[0], &a) && getintlit(args[1], &b))
- r = val(n->loc, a ^ b, exprtype(n));
- break;
- case Omemb:
- t = tybase(exprtype(args[0]));
- /* we only fold lengths right now */
- if (t->type == Tyarray && !strcmp(namestr(args[1]), "len"))
- r = t->asize;
- break;
- case Oarr:
- qsort(n->expr.args, n->expr.nargs, sizeof(Node*), idxcmp);
- break;
- case Ocast:
- r = foldcast(n);
- break;
- default:
- break;
- }
-
- if (r && n->expr.idx)
- r->expr.idx = n->expr.idx;
-
- if (r)
- return r;
- else
- return n;
+ Node **args, *r;
+ Type *t;
+ vlong a, b;
+ size_t i;
+
+ if (!n)
+ return NULL;
+ if (n->type != Nexpr)
+ return n;
+
+ r = NULL;
+ args = n->expr.args;
+ if (n->expr.idx)
+ n->expr.idx = fold(n->expr.idx, foldvar);
+ for (i = 0; i < n->expr.nargs; i++)
+ args[i] = fold(args[i], foldvar);
+ switch (exprop(n)) {
+ case Ovar:
+ if (foldvar && issmallconst(decls[n->expr.did]))
+ r = fold(decls[n->expr.did]->decl.init, foldvar);
+ break;
+ case Oadd:
+ /* x + 0 = 0 */
+ if (isintval(args[0], 0))
+ r = args[1];
+ if (isintval(args[1], 0))
+ r = args[0];
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a + b, exprtype(n));
+ break;
+ case Osub:
+ /* x - 0 = 0 */
+ if (isintval(args[1], 0))
+ r = args[0];
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a - b, exprtype(n));
+ break;
+ case Omul:
+ /* 1 * x = x */
+ if (isintval(args[0], 1))
+ r = args[1];
+ if (isintval(args[1], 1))
+ r = args[0];
+ /* 0 * x = 0 */
+ if (isintval(args[0], 0))
+ r = args[0];
+ if (isintval(args[1], 0))
+ r = args[1];
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a * b, exprtype(n));
+ break;
+ case Odiv:
+ /* x/0 = error */
+ if (isintval(args[1], 0))
+ fatal(args[1], "division by zero");
+ /* x/1 = x */
+ if (isintval(args[1], 1))
+ r = args[0];
+ /* 0/x = 0 */
+ if (isintval(args[1], 0))
+ r = args[1];
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a / b, exprtype(n));
+ break;
+ case Omod:
+ /* x%1 = x */
+ if (isintval(args[1], 0))
+ r = args[0];
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a % b, exprtype(n));
+ break;
+ case Oneg:
+ if (getintlit(args[0], &a))
+ r = val(n->loc, -a, exprtype(n));
+ break;
+ case Obsl:
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a << b, exprtype(n));
+ break;
+ case Obsr:
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a >> b, exprtype(n));
+ break;
+ case Obor:
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a | b, exprtype(n));
+ break;
+ case Oband:
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a & b, exprtype(n));
+ break;
+ case Obxor:
+ if (getintlit(args[0], &a) && getintlit(args[1], &b))
+ r = val(n->loc, a ^ b, exprtype(n));
+ break;
+ case Omemb:
+ t = tybase(exprtype(args[0]));
+ /* we only fold lengths right now */
+ if (t->type == Tyarray && !strcmp(namestr(args[1]), "len"))
+ r = t->asize;
+ break;
+ case Oarr:
+ qsort(n->expr.args, n->expr.nargs, sizeof(Node*), idxcmp);
+ break;
+ case Ocast:
+ r = foldcast(n);
+ break;
+ default:
+ break;
+ }
+
+ if (r && n->expr.idx)
+ r->expr.idx = n->expr.idx;
+
+ if (r)
+ return r;
+ else
+ return n;
}
generated by cgit v1.1 at 2021-01-27 14:19:56 +0000