From: Jan Beulich Date: Tue, 2 Aug 2016 15:51:10 +0000 (+0200) Subject: x86: use gcc6'es flags asm() output support X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~650 X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https://%22%22/%22http:/www.example.com/cgi/%22https:/%22%22?a=commitdiff_plain;h=452ec7fb73b648863dd5fe62c6134229cedef9e5;p=xen.git x86: use gcc6'es flags asm() output support ..., rendering affected code more efficient and smaller. Note that in atomic.h this at once does away with the redundant output and input specifications of the memory location touched. Signed-off-by: Jan Beulich Reviewed-by: Andrew Cooper Acked-by: Kevin Tian --- diff --git a/xen/arch/x86/x86_emulate/x86_emulate.c b/xen/arch/x86/x86_emulate/x86_emulate.c index fe594ba895..d5a56cf6c5 100644 --- a/xen/arch/x86/x86_emulate/x86_emulate.c +++ b/xen/arch/x86/x86_emulate/x86_emulate.c @@ -610,7 +610,12 @@ do { \ */ static bool_t even_parity(uint8_t v) { +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm ( "test %1,%1" : "=@ccp" (v) : "q" (v) ); +#else asm ( "test %1,%1; setp %0" : "=qm" (v) : "q" (v) ); +#endif + return v; } @@ -832,8 +837,14 @@ static int read_ulong( static bool_t mul_dbl(unsigned long m[2]) { bool_t rc; + +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm ( "mul %1" : "+a" (m[0]), "+d" (m[1]), "=@cco" (rc) ); +#else asm ( "mul %1; seto %2" : "+a" (m[0]), "+d" (m[1]), "=qm" (rc) ); +#endif + return rc; } @@ -845,8 +856,14 @@ static bool_t mul_dbl(unsigned long m[2]) static bool_t imul_dbl(unsigned long m[2]) { bool_t rc; + +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm ( "imul %1" : "+a" (m[0]), "+d" (m[1]), "=@cco" (rc) ); +#else asm ( "imul %1; seto %2" : "+a" (m[0]), "+d" (m[1]), "=qm" (rc) ); +#endif + return rc; } @@ -4650,9 +4667,15 @@ x86_emulate( case 0xbc: /* bsf or tzcnt */ { bool_t zf; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm ( "bsf %2,%0" + : "=r" (dst.val), "=@ccz" (zf) + : "rm" (src.val) ); +#else asm ( "bsf %2,%0; setz %1" : "=r" (dst.val), "=qm" (zf) : "rm" (src.val) ); +#endif _regs.eflags &= ~EFLG_ZF; if ( (vex.pfx == vex_f3) && vcpu_has_bmi1() ) { @@ -4676,9 +4699,15 @@ x86_emulate( case 0xbd: /* bsr or lzcnt */ { bool_t zf; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm ( "bsr %2,%0" + : "=r" (dst.val), "=@ccz" (zf) + : "rm" (src.val) ); +#else asm ( "bsr %2,%0; setz %1" : "=r" (dst.val), "=qm" (zf) : "rm" (src.val) ); +#endif _regs.eflags &= ~EFLG_ZF; if ( (vex.pfx == vex_f3) && vcpu_has_lzcnt() ) { diff --git a/xen/include/asm-x86/atomic.h b/xen/include/asm-x86/atomic.h index 101eded1a0..ef7e70bbbe 100644 --- a/xen/include/asm-x86/atomic.h +++ b/xen/include/asm-x86/atomic.h @@ -133,12 +133,18 @@ static inline int atomic_sub_return(int i, atomic_t *v) static inline int atomic_sub_and_test(int i, atomic_t *v) { - unsigned char c; + bool_t c; + +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; subl %2,%0" + : "+m" (*(volatile int *)&v->counter), "=@ccz" (c) + : "ir" (i) : "memory" ); +#else + asm volatile ( "lock; subl %2,%0; setz %1" + : "+m" (*(volatile int *)&v->counter), "=qm" (c) + : "ir" (i) : "memory" ); +#endif - asm volatile ( - "lock; subl %2,%0; sete %1" - : "=m" (*(volatile int *)&v->counter), "=qm" (c) - : "ir" (i), "m" (*(volatile int *)&v->counter) : "memory" ); return c; } @@ -157,13 +163,19 @@ static inline int atomic_inc_return(atomic_t *v) static inline int atomic_inc_and_test(atomic_t *v) { - unsigned char c; + bool_t c; - asm volatile ( - "lock; incl %0; sete %1" - : "=m" (*(volatile int *)&v->counter), "=qm" (c) - : "m" (*(volatile int *)&v->counter) : "memory" ); - return c != 0; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; incl %0" + : "+m" (*(volatile int *)&v->counter), "=@ccz" (c) + :: "memory" ); +#else + asm volatile ( "lock; incl %0; setz %1" + : "+m" (*(volatile int *)&v->counter), "=qm" (c) + :: "memory" ); +#endif + + return c; } static inline void atomic_dec(atomic_t *v) @@ -181,23 +193,35 @@ static inline int atomic_dec_return(atomic_t *v) static inline int atomic_dec_and_test(atomic_t *v) { - unsigned char c; + bool_t c; - asm volatile ( - "lock; decl %0; sete %1" - : "=m" (*(volatile int *)&v->counter), "=qm" (c) - : "m" (*(volatile int *)&v->counter) : "memory" ); - return c != 0; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; decl %0" + : "+m" (*(volatile int *)&v->counter), "=@ccz" (c) + :: "memory" ); +#else + asm volatile ( "lock; decl %0; setz %1" + : "+m" (*(volatile int *)&v->counter), "=qm" (c) + :: "memory" ); +#endif + + return c; } static inline int atomic_add_negative(int i, atomic_t *v) { - unsigned char c; + bool_t c; + +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; addl %2,%0" + : "+m" (*(volatile int *)&v->counter), "=@ccs" (c) + : "ir" (i) : "memory" ); +#else + asm volatile ( "lock; addl %2,%0; sets %1" + : "+m" (*(volatile int *)&v->counter), "=qm" (c) + : "ir" (i) : "memory" ); +#endif - asm volatile ( - "lock; addl %2,%0; sets %1" - : "=m" (*(volatile int *)&v->counter), "=qm" (c) - : "ir" (i), "m" (*(volatile int *)&v->counter) : "memory" ); return c; } diff --git a/xen/include/asm-x86/bitops.h b/xen/include/asm-x86/bitops.h index ff43a98fd7..a8db7e432e 100644 --- a/xen/include/asm-x86/bitops.h +++ b/xen/include/asm-x86/bitops.h @@ -145,8 +145,14 @@ static inline int test_and_set_bit(int nr, volatile void *addr) { int oldbit; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; btsl %2,%1" + : "=@ccc" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory" ); +#else asm volatile ( "lock; btsl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory"); + : "=r" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory" ); +#endif + return oldbit; } #define test_and_set_bit(nr, addr) ({ \ @@ -167,10 +173,16 @@ static inline int __test_and_set_bit(int nr, void *addr) { int oldbit; - asm volatile ( - "btsl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit), "+m" (*(int *)addr) - : "Ir" (nr) : "memory" ); +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "btsl %2,%1" + : "=@ccc" (oldbit), "+m" (*(int *)addr) + : "Ir" (nr) : "memory" ); +#else + asm volatile ( "btsl %2,%1\n\tsbbl %0,%0" + : "=r" (oldbit), "+m" (*(int *)addr) + : "Ir" (nr) : "memory" ); +#endif + return oldbit; } #define __test_and_set_bit(nr, addr) ({ \ @@ -190,8 +202,14 @@ static inline int test_and_clear_bit(int nr, volatile void *addr) { int oldbit; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; btrl %2,%1" + : "=@ccc" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory" ); +#else asm volatile ( "lock; btrl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory"); + : "=r" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory" ); +#endif + return oldbit; } #define test_and_clear_bit(nr, addr) ({ \ @@ -212,10 +230,16 @@ static inline int __test_and_clear_bit(int nr, void *addr) { int oldbit; - asm volatile ( - "btrl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit), "+m" (*(int *)addr) - : "Ir" (nr) : "memory" ); +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "btrl %2,%1" + : "=@ccc" (oldbit), "+m" (*(int *)addr) + : "Ir" (nr) : "memory" ); +#else + asm volatile ( "btrl %2,%1\n\tsbbl %0,%0" + : "=r" (oldbit), "+m" (*(int *)addr) + : "Ir" (nr) : "memory" ); +#endif + return oldbit; } #define __test_and_clear_bit(nr, addr) ({ \ @@ -228,10 +252,16 @@ static inline int __test_and_change_bit(int nr, void *addr) { int oldbit; - asm volatile ( - "btcl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit), "+m" (*(int *)addr) - : "Ir" (nr) : "memory" ); +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "btcl %2,%1" + : "=@ccc" (oldbit), "+m" (*(int *)addr) + : "Ir" (nr) : "memory" ); +#else + asm volatile ( "btcl %2,%1\n\tsbbl %0,%0" + : "=r" (oldbit), "+m" (*(int *)addr) + : "Ir" (nr) : "memory" ); +#endif + return oldbit; } #define __test_and_change_bit(nr, addr) ({ \ @@ -251,8 +281,14 @@ static inline int test_and_change_bit(int nr, volatile void *addr) { int oldbit; +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "lock; btcl %2,%1" + : "=@ccc" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory" ); +#else asm volatile ( "lock; btcl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory"); + : "=r" (oldbit), "+m" (ADDR) : "Ir" (nr) : "memory" ); +#endif + return oldbit; } #define test_and_change_bit(nr, addr) ({ \ @@ -270,10 +306,16 @@ static inline int variable_test_bit(int nr, const volatile void *addr) { int oldbit; - asm volatile ( - "btl %2,%1\n\tsbbl %0,%0" - : "=r" (oldbit) - : "m" (CONST_ADDR), "Ir" (nr) : "memory" ); +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + asm volatile ( "btl %2,%1" + : "=@ccc" (oldbit) + : "m" (CONST_ADDR), "Ir" (nr) : "memory" ); +#else + asm volatile ( "btl %2,%1\n\tsbbl %0,%0" + : "=r" (oldbit) + : "m" (CONST_ADDR), "Ir" (nr) : "memory" ); +#endif + return oldbit; } diff --git a/xen/include/asm-x86/hvm/vmx/vmx.h b/xen/include/asm-x86/hvm/vmx/vmx.h index 359b2a9830..4cdd9b1d9f 100644 --- a/xen/include/asm-x86/hvm/vmx/vmx.h +++ b/xen/include/asm-x86/hvm/vmx/vmx.h @@ -406,12 +406,17 @@ static inline bool_t __vmread_safe(unsigned long field, unsigned long *value) VMREAD_OPCODE MODRM_EAX_ECX #endif /* CF==1 or ZF==1 --> rc = 0 */ +#ifdef __GCC_ASM_FLAG_OUTPUTS__ + : "=@ccnbe" (okay), +#else "setnbe %0" + : "=qm" (okay), +#endif #ifdef HAVE_GAS_VMX - : "=qm" (okay), "=rm" (*value) + "=rm" (*value) : "r" (field)); #else - : "=qm" (okay), "=c" (*value) + "=c" (*value) : "a" (field)); #endif