From: Russ Cox Date: Mon, 8 Sep 2014 03:40:59 +0000 (-0400) Subject: runtime: implement time.now in assembly on plan9, solaris, windows X-Git-Tag: go1.4beta1~492 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=13d0b82bc8821c41ec3782d0d5911cda2499dedc;p=gostls13.git runtime: implement time.now in assembly on plan9, solaris, windows These all used a C implementation that contained 64-bit divide by 1000000000. On 32-bit systems that ends up in the 64-bit C divide support, which makes other calls and ends up using a fair amount of stack. We could convert them to Go but then they'd still end up in software 64-bit divide code. That would be okay, because Go code can split the stack, but it's still unnecessary. Write time·now in assembly, just like on all the other systems, and use the actual hardware support for 64/32 -> 64/32 division. This cuts the software routines out entirely. The actual code to do the division is copied and pasted from the sys_darwin_*.s files. LGTM=alex.brainman R=golang-codereviews, alex.brainman CC=aram, golang-codereviews, iant, khr, r https://golang.org/cl/136300043 --- diff --git a/src/pkg/runtime/os_plan9.c b/src/pkg/runtime/os_plan9.c index f824710793..853f3ef7a1 100644 --- a/src/pkg/runtime/os_plan9.c +++ b/src/pkg/runtime/os_plan9.c @@ -160,19 +160,6 @@ runtime·nanotime(void) return ns; } -#pragma textflag NOSPLIT -void -time·now(int64 sec, int32 nsec) -{ - int64 ns; - - ns = runtime·nanotime(); - sec = ns / 1000000000LL; - nsec = ns - sec * 1000000000LL; - FLUSH(&sec); - FLUSH(&nsec); -} - #pragma textflag NOSPLIT void runtime·itoa(int32 n, byte *p, uint32 len) diff --git a/src/pkg/runtime/os_solaris.c b/src/pkg/runtime/os_solaris.c index c6c2a8a7a1..e35d2b9971 100644 --- a/src/pkg/runtime/os_solaris.c +++ b/src/pkg/runtime/os_solaris.c @@ -436,19 +436,6 @@ runtime·nanotime(void) return runtime·sysvicall0((uintptr)runtime·nanotime1); } -#pragma textflag NOSPLIT -void -time·now(int64 sec, int32 usec) -{ - int64 ns; - - ns = runtime·nanotime(); - sec = ns / 1000000000LL; - usec = ns - sec * 1000000000LL; - FLUSH(&sec); - FLUSH(&usec); -} - #pragma textflag NOSPLIT int32 runtime·open(int8* path, int32 oflag, int32 mode) diff --git a/src/pkg/runtime/os_windows.c b/src/pkg/runtime/os_windows.c index d7f7a5a3b4..a4d77f6b75 100644 --- a/src/pkg/runtime/os_windows.c +++ b/src/pkg/runtime/os_windows.c @@ -301,6 +301,13 @@ runtime·systime(KSYSTEM_TIME *timeaddr) return 0; } +#pragma textflag NOSPLIT +int64 +runtime·unixnano(void) +{ + return (runtime·systime(SYSTEM_TIME) - 116444736000000000LL) * 100LL; +} + static void badsystime(void) { @@ -314,22 +321,6 @@ runtime·nanotime(void) return runtime·systime(INTERRUPT_TIME) * 100LL; } -#pragma textflag NOSPLIT -void -time·now(int64 sec, int32 usec) -{ - int64 ns; - - // SystemTime is 100s of nanoseconds since January 1, 1601. - // Convert to nanoseconds since January 1, 1970. - ns = (runtime·systime(SYSTEM_TIME) - 116444736000000000LL) * 100LL; - - sec = ns / 1000000000LL; - usec = ns - sec * 1000000000LL; - FLUSH(&sec); - FLUSH(&usec); -} - // Calling stdcall on os stack. #pragma textflag NOSPLIT static void* diff --git a/src/pkg/runtime/sys_darwin_amd64.s b/src/pkg/runtime/sys_darwin_amd64.s index 2f98bfb06c..bd397d72a7 100644 --- a/src/pkg/runtime/sys_darwin_amd64.s +++ b/src/pkg/runtime/sys_darwin_amd64.s @@ -158,7 +158,7 @@ TEXT runtime·nanotime(SB),NOSPLIT,$0-8 RET // func now() (sec int64, nsec int32) -TEXT time·now(SB),NOSPLIT,$8 +TEXT time·now(SB),NOSPLIT,$0-12 CALL nanotime<>(SB) // generated code for diff --git a/src/pkg/runtime/sys_plan9_386.s b/src/pkg/runtime/sys_plan9_386.s index dfa09613e4..7432981813 100644 --- a/src/pkg/runtime/sys_plan9_386.s +++ b/src/pkg/runtime/sys_plan9_386.s @@ -101,6 +101,19 @@ TEXT runtime·nsec(SB),NOSPLIT,$8 MOVL $-1, ret_hi+8(FP) RET +// func now() (sec int64, nsec int32) +TEXT time·now(SB),NOSPLIT,$8-12 + CALL runtime·nanotime(SB) + MOVL 0(SP), AX + MOVL 4(SP), DX + + MOVL $1000000000, CX + DIVL CX + MOVL AX, sec+0(FP) + MOVL $0, sec+4(FP) + MOVL DX, nsec+8(FP) + RET + TEXT runtime·notify(SB),NOSPLIT,$0 MOVL $28, AX INT $64 diff --git a/src/pkg/runtime/sys_plan9_amd64.s b/src/pkg/runtime/sys_plan9_amd64.s index 08ddc3ffa8..954c0c27bb 100644 --- a/src/pkg/runtime/sys_plan9_amd64.s +++ b/src/pkg/runtime/sys_plan9_amd64.s @@ -91,6 +91,26 @@ TEXT runtime·nsec(SB),NOSPLIT,$0 MOVQ AX, ret+8(FP) RET +// func now() (sec int64, nsec int32) +TEXT time·now(SB),NOSPLIT,$8-12 + CALL runtime·nanotime(SB) + MOVQ 0(SP), AX + + // generated code for + // func f(x uint64) (uint64, uint64) { return x/1000000000, x%100000000 } + // adapted to reduce duplication + MOVQ AX, CX + MOVQ $1360296554856532783, AX + MULQ CX + ADDQ CX, DX + RCRQ $1, DX + SHRQ $29, DX + MOVQ DX, sec+0(FP) + IMULQ $1000000000, DX + SUBQ DX, CX + MOVL CX, nsec+8(FP) + RET + TEXT runtime·notify(SB),NOSPLIT,$0 MOVQ $28, BP SYSCALL diff --git a/src/pkg/runtime/sys_solaris_amd64.s b/src/pkg/runtime/sys_solaris_amd64.s index 2055d6c80b..093315c4a4 100644 --- a/src/pkg/runtime/sys_solaris_amd64.s +++ b/src/pkg/runtime/sys_solaris_amd64.s @@ -327,3 +327,23 @@ TEXT runtime·osyield1(SB),NOSPLIT,$0 MOVQ libc·sched_yield(SB), AX CALL AX RET + +// func now() (sec int64, nsec int32) +TEXT time·now(SB),NOSPLIT,$8-12 + CALL runtime·nanotime(SB) + MOVQ 0(SP), AX + + // generated code for + // func f(x uint64) (uint64, uint64) { return x/1000000000, x%100000000 } + // adapted to reduce duplication + MOVQ AX, CX + MOVQ $1360296554856532783, AX + MULQ CX + ADDQ CX, DX + RCRQ $1, DX + SHRQ $29, DX + MOVQ DX, sec+0(FP) + IMULQ $1000000000, DX + SUBQ DX, CX + MOVL CX, nsec+8(FP) + RET diff --git a/src/pkg/runtime/sys_windows_386.s b/src/pkg/runtime/sys_windows_386.s index f4d561feea..a9e096f018 100644 --- a/src/pkg/runtime/sys_windows_386.s +++ b/src/pkg/runtime/sys_windows_386.s @@ -365,3 +365,16 @@ TEXT runtime·usleep2(SB),NOSPLIT,$20 CALL AX MOVL BP, SP RET + +// func now() (sec int64, nsec int32) +TEXT time·now(SB),NOSPLIT,$8-12 + CALL runtime·unixnano(SB) + MOVL 0(SP), AX + MOVL 4(SP), DX + + MOVL $1000000000, CX + DIVL CX + MOVL AX, sec+0(FP) + MOVL $0, sec+4(FP) + MOVL DX, nsec+8(FP) + RET diff --git a/src/pkg/runtime/sys_windows_amd64.s b/src/pkg/runtime/sys_windows_amd64.s index e5890e04ae..21f73daf09 100644 --- a/src/pkg/runtime/sys_windows_amd64.s +++ b/src/pkg/runtime/sys_windows_amd64.s @@ -384,3 +384,24 @@ TEXT runtime·usleep2(SB),NOSPLIT,$16 CALL AX MOVQ 8(SP), SP RET + +// func now() (sec int64, nsec int32) +TEXT time·now(SB),NOSPLIT,$8-12 + CALL runtime·unixnano(SB) + MOVQ 0(SP), AX + + // generated code for + // func f(x uint64) (uint64, uint64) { return x/1000000000, x%100000000 } + // adapted to reduce duplication + MOVQ AX, CX + MOVQ $1360296554856532783, AX + MULQ CX + ADDQ CX, DX + RCRQ $1, DX + SHRQ $29, DX + MOVQ DX, sec+0(FP) + IMULQ $1000000000, DX + SUBQ DX, CX + MOVL CX, nsec+8(FP) + RET +