various relocation related optimization

With 59ca5a8db, querying if a symbol is defined is cheap. If we're
compiling code that calls foo() and we defined foo() in this compilation
unit, we already know its offset within the .text section, so use it
instead of emitting a relocation for the linker to handle.  Also, put
small literal data in the .text section instead of .rodata.  This seems
to improve performance (cache locality?), and as a bonus, it will be
good for aarch64's instr encoding with smallish PC-relative offsets.

1 files changed, 3 insertions, 3 deletions

diff --git a/c/c.c b/c/c.c
index 5ff2041..4c4868b 100644
--- a/c/c.c
+++ b/c/c.c
@@ -4308,8 +4308,8 @@ function(struct comp *cm, struct function *fn, const char **pnames, const struct
       if (!ifunc) ifunc = intern("__func__");
       union type ty = mkarrtype(mktype(TYCHAR), QCONST, strlen(fn->name) + 1);
       const char *sym = mkhiddensym(fn->name, ifunc, 1);
-      uint off = objnewdat(sym, Srodata, 0, typesize(ty), typealign(ty));
-      uchar *p = objout.rodata.p + off;
+      uint off = objnewdat(sym, Stext, 0, typesize(ty), typealign(ty));
+      uchar *p = objout.textbegin + off;
       memcpy(p, fn->name, typearrlen(ty)-1);
       putdecl(cm, &(struct decl) {
          .ty = ty, .qual = QCONST,
@@ -4418,7 +4418,7 @@ docomp(struct comp *cm)
                pdecl(&st, cm);
             } else if (decl.ty.t != TYFUNC && decl.scls != SCTYPEDEF && (decl.scls != SCEXTERN || noscls)) {
                /* tentative definitions */
-               if (!objhassym(decl.sym)) {
+               if (!objhassym(decl.sym, NULL)) {
                   uint size = typesize(d->ty);
                   if (isincomplete(d->ty)) {
                      if (d->ty.t == TYARRAY) {