From: Rich Felker <dalias@aerifal.cx>
Date: Tue, 16 Oct 2018 18:08:01 +0000 (-0400)
Subject: make thread-pointer-loading asm non-volatile
X-Git-Tag: v1.1.21~49
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=a4a3e4dbc086eb58e5cf6118480ef4825788e231;p=oweals%2Fmusl.git

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.
---

diff --git a/arch/aarch64/pthread_arch.h b/arch/aarch64/pthread_arch.h
index e8499d8e..e64b126d 100644
--- a/arch/aarch64/pthread_arch.h
+++ b/arch/aarch64/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	char *self;
-	__asm__ __volatile__ ("mrs %0,tpidr_el0" : "=r"(self));
+	__asm__ ("mrs %0,tpidr_el0" : "=r"(self));
 	return (void*)(self - sizeof(struct pthread));
 }
 
diff --git a/arch/arm/pthread_arch.h b/arch/arm/pthread_arch.h
index 5c6aff28..e689ea21 100644
--- a/arch/arm/pthread_arch.h
+++ b/arch/arm/pthread_arch.h
@@ -4,7 +4,7 @@
 static inline pthread_t __pthread_self()
 {
 	char *p;
-	__asm__ __volatile__ ( "mrc p15,0,%0,c13,c0,3" : "=r"(p) );
+	__asm__ ( "mrc p15,0,%0,c13,c0,3" : "=r"(p) );
 	return (void *)(p-sizeof(struct pthread));
 }
 
@@ -20,7 +20,7 @@ static inline pthread_t __pthread_self()
 {
 	extern hidden uintptr_t __a_gettp_ptr;
 	register uintptr_t p __asm__("r0");
-	__asm__ __volatile__ ( BLX " %1" : "=r"(p) : "r"(__a_gettp_ptr) : "cc", "lr" );
+	__asm__ ( BLX " %1" : "=r"(p) : "r"(__a_gettp_ptr) : "cc", "lr" );
 	return (void *)(p-sizeof(struct pthread));
 }
 
diff --git a/arch/i386/pthread_arch.h b/arch/i386/pthread_arch.h
index 7f38a562..6f600b9e 100644
--- a/arch/i386/pthread_arch.h
+++ b/arch/i386/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	struct pthread *self;
-	__asm__ __volatile__ ("movl %%gs:0,%0" : "=r" (self) );
+	__asm__ ("movl %%gs:0,%0" : "=r" (self) );
 	return self;
 }
 
diff --git a/arch/microblaze/pthread_arch.h b/arch/microblaze/pthread_arch.h
index 08d1ba7d..f6ba8de9 100644
--- a/arch/microblaze/pthread_arch.h
+++ b/arch/microblaze/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	struct pthread *self;
-	__asm__ __volatile__ ("ori %0, r21, 0" : "=r" (self) );
+	__asm__ ("ori %0, r21, 0" : "=r" (self) );
 	return self;
 }
 
diff --git a/arch/mips/pthread_arch.h b/arch/mips/pthread_arch.h
index 5fea15ad..1e7839ea 100644
--- a/arch/mips/pthread_arch.h
+++ b/arch/mips/pthread_arch.h
@@ -2,10 +2,10 @@ static inline struct pthread *__pthread_self()
 {
 #if __mips_isa_rev < 2
 	register char *tp __asm__("$3");
-	__asm__ __volatile__ (".word 0x7c03e83b" : "=r" (tp) );
+	__asm__ (".word 0x7c03e83b" : "=r" (tp) );
 #else
 	char *tp;
-	__asm__ __volatile__ ("rdhwr %0, $29" : "=r" (tp) );
+	__asm__ ("rdhwr %0, $29" : "=r" (tp) );
 #endif
 	return (pthread_t)(tp - 0x7000 - sizeof(struct pthread));
 }
diff --git a/arch/mips64/pthread_arch.h b/arch/mips64/pthread_arch.h
index 5fea15ad..1e7839ea 100644
--- a/arch/mips64/pthread_arch.h
+++ b/arch/mips64/pthread_arch.h
@@ -2,10 +2,10 @@ static inline struct pthread *__pthread_self()
 {
 #if __mips_isa_rev < 2
 	register char *tp __asm__("$3");
-	__asm__ __volatile__ (".word 0x7c03e83b" : "=r" (tp) );
+	__asm__ (".word 0x7c03e83b" : "=r" (tp) );
 #else
 	char *tp;
-	__asm__ __volatile__ ("rdhwr %0, $29" : "=r" (tp) );
+	__asm__ ("rdhwr %0, $29" : "=r" (tp) );
 #endif
 	return (pthread_t)(tp - 0x7000 - sizeof(struct pthread));
 }
diff --git a/arch/mipsn32/pthread_arch.h b/arch/mipsn32/pthread_arch.h
index 5fea15ad..1e7839ea 100644
--- a/arch/mipsn32/pthread_arch.h
+++ b/arch/mipsn32/pthread_arch.h
@@ -2,10 +2,10 @@ static inline struct pthread *__pthread_self()
 {
 #if __mips_isa_rev < 2
 	register char *tp __asm__("$3");
-	__asm__ __volatile__ (".word 0x7c03e83b" : "=r" (tp) );
+	__asm__ (".word 0x7c03e83b" : "=r" (tp) );
 #else
 	char *tp;
-	__asm__ __volatile__ ("rdhwr %0, $29" : "=r" (tp) );
+	__asm__ ("rdhwr %0, $29" : "=r" (tp) );
 #endif
 	return (pthread_t)(tp - 0x7000 - sizeof(struct pthread));
 }
diff --git a/arch/or1k/pthread_arch.h b/arch/or1k/pthread_arch.h
index 521b9c53..1b806f89 100644
--- a/arch/or1k/pthread_arch.h
+++ b/arch/or1k/pthread_arch.h
@@ -3,10 +3,10 @@ static inline struct pthread *__pthread_self()
 {
 #ifdef __clang__
 	char *tp;
-	__asm__ __volatile__ ("l.ori %0, r10, 0" : "=r" (tp) );
+	__asm__ ("l.ori %0, r10, 0" : "=r" (tp) );
 #else
 	register char *tp __asm__("r10");
-	__asm__ __volatile__ ("" : "=r" (tp) );
+	__asm__ ("" : "=r" (tp) );
 #endif
 	return (struct pthread *) (tp - sizeof(struct pthread));
 }
diff --git a/arch/powerpc/pthread_arch.h b/arch/powerpc/pthread_arch.h
index bab2e6ca..ae0f28d6 100644
--- a/arch/powerpc/pthread_arch.h
+++ b/arch/powerpc/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	register char *tp __asm__("r2");
-	__asm__ __volatile__ ("" : "=r" (tp) );
+	__asm__ ("" : "=r" (tp) );
 	return (pthread_t)(tp - 0x7000 - sizeof(struct pthread));
 }
                         
diff --git a/arch/powerpc64/pthread_arch.h b/arch/powerpc64/pthread_arch.h
index 37b75e29..79c3ecd8 100644
--- a/arch/powerpc64/pthread_arch.h
+++ b/arch/powerpc64/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	register char *tp __asm__("r13");
-	__asm__ __volatile__ ("" : "=r" (tp) );
+	__asm__ ("" : "=r" (tp) );
 	return (pthread_t)(tp - 0x7000 - sizeof(struct pthread));
 }
 
diff --git a/arch/s390x/pthread_arch.h b/arch/s390x/pthread_arch.h
index bd90016d..e2251f1f 100644
--- a/arch/s390x/pthread_arch.h
+++ b/arch/s390x/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	struct pthread *self;
-	__asm__ __volatile__ (
+	__asm__ (
 		"ear  %0, %%a0\n"
 		"sllg %0, %0, 32\n"
 		"ear  %0, %%a1\n"
diff --git a/arch/sh/pthread_arch.h b/arch/sh/pthread_arch.h
index a7dd27a6..3ee9c1a9 100644
--- a/arch/sh/pthread_arch.h
+++ b/arch/sh/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	char *self;
-	__asm__ __volatile__ ("stc gbr,%0" : "=r" (self) );
+	__asm__ ("stc gbr,%0" : "=r" (self) );
 	return (struct pthread *) (self - sizeof(struct pthread));
 }
 
diff --git a/arch/x32/pthread_arch.h b/arch/x32/pthread_arch.h
index 267ad073..f640a1a1 100644
--- a/arch/x32/pthread_arch.h
+++ b/arch/x32/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	struct pthread *self;
-	__asm__ __volatile__ ("mov %%fs:0,%0" : "=r" (self) );
+	__asm__ ("mov %%fs:0,%0" : "=r" (self) );
 	return self;
 }
 
diff --git a/arch/x86_64/pthread_arch.h b/arch/x86_64/pthread_arch.h
index c61509cf..65e880c6 100644
--- a/arch/x86_64/pthread_arch.h
+++ b/arch/x86_64/pthread_arch.h
@@ -1,7 +1,7 @@
 static inline struct pthread *__pthread_self()
 {
 	struct pthread *self;
-	__asm__ __volatile__ ("mov %%fs:0,%0" : "=r" (self) );
+	__asm__ ("mov %%fs:0,%0" : "=r" (self) );
 	return self;
 }