simplify dlstart code by using integer type for base address

src/ldso/dlstart.c

@@ -21,6 +21,7 @@ __attribute__((__visibility__("hidden")))
 void _dlstart_c(size_t *sp, size_t *dynv)
 {
 	size_t i, aux[AUX_CNT], dyn[DYN_CNT];
+	size_t *rel, rel_size, base;
 
 	int argc = *sp;
 	char **argv = (void *)(sp+1);
@@ -40,14 +41,14 @@ void _dlstart_c(size_t *sp, size_t *dynv)
 	 * address is not available in the aux vector. Instead, compute
 	 * the load address as the difference between &_DYNAMIC and the
 	 * virtual address in the PT_DYNAMIC program header. */
-	unsigned char *base = (void *)aux[AT_BASE];
+	base = aux[AT_BASE];
 	if (!base) {
 		size_t phnum = aux[AT_PHNUM];
 		size_t phentsize = aux[AT_PHENT];
 		Phdr *ph = (void *)aux[AT_PHDR];
 		for (i=phnum; i--; ph = (void *)((char *)ph + phentsize)) {
 			if (ph->p_type == PT_DYNAMIC) {
-				base = (void *)((size_t)dynv - ph->p_vaddr);
+				base = (size_t)dynv - ph->p_vaddr;
 				break;
 			}
 		}
@@ -61,17 +62,15 @@ void _dlstart_c(size_t *sp, size_t *dynv)
 		size_t *got = (void *)(base + dyn[DT_PLTGOT]);
 		for (i=0; dynv[i]; i+=2) if (dynv[i]==DT_MIPS_LOCAL_GOTNO)
 			local_cnt = dynv[i+1];
-		for (i=0; i<local_cnt; i++) got[i] += (size_t)base;
+		for (i=0; i<local_cnt; i++) got[i] += base;
 	}
 
-	size_t *rel, rel_size;
-
 	rel = (void *)(base+dyn[DT_REL]);
 	rel_size = dyn[DT_RELSZ];
 	for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t)) {
 		if (!IS_RELATIVE(rel[1])) continue;
 		size_t *rel_addr = (void *)(base + rel[0]);
-		*rel_addr += (size_t)base;
+		*rel_addr += base;
 	}
 
 	rel = (void *)(base+dyn[DT_RELA]);
@@ -79,12 +78,12 @@ void _dlstart_c(size_t *sp, size_t *dynv)
 	for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
 		if (!IS_RELATIVE(rel[1])) continue;
 		size_t *rel_addr = (void *)(base + rel[0]);
-		*rel_addr = (size_t)base + rel[2];
+		*rel_addr = base + rel[2];
 	}
 
 	stage2_func dls2;
 	GETFUNCSYM(&dls2, __dls2, base+dyn[DT_PLTGOT]);
-	dls2(base, sp);
+	dls2((void *)base, sp);
 }
 
 #endif