[hackers] [scc/qbe] [cc2-qbe] Add cast() || Roberto E. Vargas Caballero

From: <git_AT_suckless.org>
Date: Wed, 17 Aug 2016 14:29:50 +0200 (CEST)

commit fa9a898e3d16f7f133e563e0cdd36a24724359d9
Author: Roberto E. Vargas Caballero <k0ga_AT_shike2.com>
AuthorDate: Tue Aug 16 09:10:13 2016 +0200
Commit: Roberto E. Vargas Caballero <k0ga_AT_shike2.com>
CommitDate: Wed Aug 17 14:29:25 2016 +0200

    [cc2-qbe] Add cast()
    
    This code is directly taken and adapted from the old
    cgen for qbe.

diff --git a/cc2/arch/qbe/cgen.c b/cc2/arch/qbe/cgen.c
index 096089e..2e52dc4 100644
--- a/cc2/arch/qbe/cgen.c
+++ b/cc2/arch/qbe/cgen.c
_AT_@ -90,7 +90,7 @@ static char opasmd[] = {
         [OCPL] = ASCPLD
 };
 
-extern Type int32type;
+extern Type int32type, uint32type;
 
 static Node *
 tmpnode(Node *np, Type *tp)
_AT_@ -136,6 +136,80 @@ load(Node *np, Node *new)
         return new;
 }
 
+static Node *rhs(Node *np, Node *new);
+
+static Node *
+cast(Type *td, Node *ns, Node *nd)
+{
+ Type *ts;
+ Node aux1, aux2;
+ int op, d_isint, s_isint;
+
+ ts = &ns->type;
+ d_isint = (td->flags & INTF) != 0;
+ s_isint = (ts->flags & INTF) != 0;
+
+ if (d_isint && s_isint) {
+ if (td->size <= ts->size)
+ return nd;
+ assert(td->size == 4 || td->size == 8);
+ switch (ts->size) {
+ case 1:
+ op = (td->size == 4) ? ASEXTBW : ASEXTBL;
+ break;
+ case 2:
+ op = (td->size == 4) ? ASEXTHW : ASEXTHL;
+ break;
+ case 4:
+ op = ASEXTWL;
+ break;
+ default:
+ abort();
+ }
+ /*
+ * unsigned version of operations are always +1 the
+ * signed version
+ */
+ op += (td->flags & SIGNF) == 0;
+ } else if (d_isint) {
+ /* conversion from float to int */
+ switch (ts->size) {
+ case 4:
+ op = (td->size == 8) ? ASSTOL : ASSTOW;
+ break;
+ case 8:
+ op = (td->size == 8) ? ASDTOL : ASDTOW;
+ break;
+ default:
+ abort();
+ }
+ /* TODO: Add signess */
+ } else if (s_isint) {
+ /* conversion from int to float */
+ switch (ts->size) {
+ case 1:
+ case 2:
+ ts = (ts->flags&SIGNF) ? &int32type : &uint32type;
+ ns = cast(ts, ns, tmpnode(&aux2, ts));
+ case 4:
+ op = (td->size == 8) ? ASSWTOD : ASSWTOS;
+ break;
+ case 8:
+ op = (td->size == 8) ? ASSLTOD : ASSLTOS;
+ break;
+ default:
+ abort();
+ }
+ /* TODO: Add signess */
+ } else {
+ /* conversion from float to float */
+ op = (td->size == 4) ? ASEXTS : ASTRUNCD;
+ }
+
+ code(op, tmpnode(nd, td), ns, NULL);
+ return nd;
+}
+
 static Node *
 assign(Node *to, Node *from)
 {
_AT_@ -323,6 +397,8 @@ rhs(Node *np, Node *ret)
                 tmpnode(ret, tp);
                 code(op, ret, &aux1, &aux2);
                 return ret;
+ case OCAST:
+ return cast(tp, rhs(l, &aux1), ret);
         case OASSIG:
                 lhs(l, &aux1);
                 rhs(r, ret);
Received on Wed Aug 17 2016 - 14:29:50 CEST