musl/arch/s390x/pthread_arch.h

static inline struct pthread *__pthread_self()
{
	struct pthread *self;
	__asm__ (
		"ear  %0, %%a0\n"
		"sllg %0, %0, 32\n"
		"ear  %0, %%a1\n"
		: "=r"(self));
	return self;
}

#define MC_PC psw.addr
add s390x port 2016-11-12 03:52:05 +00:00			`static inline struct pthread *__pthread_self()`
			`{`
			`struct pthread *self;`
make thread-pointer-loading asm non-volatile this will allow the compiler to cache and reuse the result, meaning we no longer have to take care not to load it more than once for the sake of archs where the load may be expensive. depends on commit 1c84c99913bf1cd47b866ed31e665848a0da84a2 for correctness, since otherwise the compiler could hoist loads during stage 3 of dynamic linking before the initial thread-pointer setup. 2018-10-16 18:08:01 +00:00			`__asm__ (`
add s390x port 2016-11-12 03:52:05 +00:00			`"ear %0, %%a0\n"`
			`"sllg %0, %0, 32\n"`
			`"ear %0, %%a1\n"`
			`: "=r"(self));`
			`return self;`
			`}`

			`#define MC_PC psw.addr`