Allow a couple more swab implementation details through.
We hadn't spotted these before because no-one's using them, but C23 makes
the use of undeclared identifiers (in the also-unused caller) an error.
Change-Id: Iad5f364424e5621280d679aa2530e0e872abbb85
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 06afb25..a71318e 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -133,6 +133,9 @@
# These are required to support the above functions.
"__fswahw32",
"__fswahb32",
+ # As are these, for ILP32.
+ "__arch_swab32",
+ "__arch_swab64",
# This is used by various macros in <linux/ioprio.h>.
"ioprio_value",
diff --git a/libc/kernel/uapi/asm-arm/asm/swab.h b/libc/kernel/uapi/asm-arm/asm/swab.h
index 7684c22..3fff953 100644
--- a/libc/kernel/uapi/asm-arm/asm/swab.h
+++ b/libc/kernel/uapi/asm-arm/asm/swab.h
@@ -11,7 +11,18 @@
#ifndef __STRICT_ANSI__
#define __SWAB_64_THRU_32__
#endif
+static inline __attribute__((__const__)) __u32 __arch_swab32(__u32 x) {
+ __u32 t;
#ifndef __thumb__
+ if(! __builtin_constant_p(x)) {
+ asm("eor\t%0, %1, %1, ror #16" : "=r" (t) : "r" (x));
+ } else
#endif
+ t = x ^ ((x << 16) | (x >> 16));
+ x = (x << 24) | (x >> 8);
+ t &= ~0x00FF0000;
+ x ^= (t >> 8);
+ return x;
+}
#define __arch_swab32 __arch_swab32
#endif
diff --git a/libc/kernel/uapi/asm-x86/asm/swab.h b/libc/kernel/uapi/asm-x86/asm/swab.h
index 31c850d..ce43658 100644
--- a/libc/kernel/uapi/asm-x86/asm/swab.h
+++ b/libc/kernel/uapi/asm-x86/asm/swab.h
@@ -8,9 +8,27 @@
#define _ASM_X86_SWAB_H
#include <linux/types.h>
#include <linux/compiler.h>
+static inline __attribute__((__const__)) __u32 __arch_swab32(__u32 val) {
+ asm("bswapl %0" : "=r" (val) : "0" (val));
+ return val;
+}
#define __arch_swab32 __arch_swab32
+static inline __attribute__((__const__)) __u64 __arch_swab64(__u64 val) {
#ifdef __i386__
+ union {
+ struct {
+ __u32 a;
+ __u32 b;
+ } s;
+ __u64 u;
+ } v;
+ v.u = val;
+ asm("bswapl %0; bswapl %1; xchgl %0,%1" : "=r" (v.s.a), "=r" (v.s.b) : "0" (v.s.a), "1" (v.s.b));
+ return v.u;
#else
+ asm("bswapq %0" : "=r" (val) : "0" (val));
+ return val;
#endif
+}
#define __arch_swab64 __arch_swab64
#endif