blob: 13362012dd6cd98aa1a36cab43bea00c80bea64b [file] [log] [blame]
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "go_asm.h"
#include "go_tls.h"
#include "funcdata.h"
#include "textflag.h"
TEXT runtime·rt0_go(SB),NOSPLIT,$0
// copy arguments forward on an even stack
MOVL argc+0(FP), AX
MOVL argv+4(FP), BX
SUBL $128, SP // plenty of scratch
ANDL $~15, SP
MOVL AX, 120(SP) // save argc, argv away
MOVL BX, 124(SP)
// set default stack bounds.
// _cgo_init may update stackguard.
MOVL $runtime·g0(SB), BP
LEAL (-64*1024+104)(SP), BX
MOVL BX, g_stackguard0(BP)
MOVL BX, g_stackguard1(BP)
MOVL BX, (g_stack+stack_lo)(BP)
MOVL SP, (g_stack+stack_hi)(BP)
// find out information about the processor we're on
MOVL $0, AX
CPUID
CMPL AX, $0
JE nocpuinfo
// Figure out how to serialize RDTSC.
// On Intel processors LFENCE is enough. AMD requires MFENCE.
// Don't know about the rest, so let's do MFENCE.
CMPL BX, $0x756E6547 // "Genu"
JNE notintel
CMPL DX, $0x49656E69 // "ineI"
JNE notintel
CMPL CX, $0x6C65746E // "ntel"
JNE notintel
MOVB $1, runtime·lfenceBeforeRdtsc(SB)
notintel:
MOVL $1, AX
CPUID
MOVL CX, runtime·cpuid_ecx(SB)
MOVL DX, runtime·cpuid_edx(SB)
nocpuinfo:
// if there is an _cgo_init, call it to let it
// initialize and to set up GS. if not,
// we set up GS ourselves.
MOVL _cgo_init(SB), AX
TESTL AX, AX
JZ needtls
MOVL $setg_gcc<>(SB), BX
MOVL BX, 4(SP)
MOVL BP, 0(SP)
CALL AX
// update stackguard after _cgo_init
MOVL $runtime·g0(SB), CX
MOVL (g_stack+stack_lo)(CX), AX
ADDL $const__StackGuard, AX
MOVL AX, g_stackguard0(CX)
MOVL AX, g_stackguard1(CX)
// skip runtime·ldt0setup(SB) and tls test after _cgo_init for non-windows
CMPL runtime·iswindows(SB), $0
JEQ ok
needtls:
// skip runtime·ldt0setup(SB) and tls test on Plan 9 in all cases
CMPL runtime·isplan9(SB), $1
JEQ ok
// set up %gs
CALL runtime·ldt0setup(SB)
// store through it, to make sure it works
get_tls(BX)
MOVL $0x123, g(BX)
MOVL runtime·tls0(SB), AX
CMPL AX, $0x123
JEQ ok
MOVL AX, 0 // abort
ok:
// set up m and g "registers"
get_tls(BX)
LEAL runtime·g0(SB), CX
MOVL CX, g(BX)
LEAL runtime·m0(SB), AX
// save m->g0 = g0
MOVL CX, m_g0(AX)
// save g0->m = m0
MOVL AX, g_m(CX)
CALL runtime·emptyfunc(SB) // fault if stack check is wrong
// convention is D is always cleared
CLD
CALL runtime·check(SB)
// saved argc, argv
MOVL 120(SP), AX
MOVL AX, 0(SP)
MOVL 124(SP), AX
MOVL AX, 4(SP)
CALL runtime·args(SB)
CALL runtime·osinit(SB)
CALL runtime·schedinit(SB)
// create a new goroutine to start program
PUSHL $runtime·mainPC(SB) // entry
PUSHL $0 // arg size
CALL runtime·newproc(SB)
POPL AX
POPL AX
// start this M
CALL runtime·mstart(SB)
INT $3
RET
DATA runtime·mainPC+0(SB)/4,$runtime·main(SB)
GLOBL runtime·mainPC(SB),RODATA,$4
TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
INT $3
RET
TEXT runtime·asminit(SB),NOSPLIT,$0-0
// Linux and MinGW start the FPU in extended double precision.
// Other operating systems use double precision.
// Change to double precision to match them,
// and to match other hardware that only has double.
PUSHL $0x27F
FLDCW 0(SP)
POPL AX
RET
/*
* go-routine
*/
// void gosave(Gobuf*)
// save state in Gobuf; setjmp
TEXT runtime·gosave(SB), NOSPLIT, $0-4
MOVL buf+0(FP), AX // gobuf
LEAL buf+0(FP), BX // caller's SP
MOVL BX, gobuf_sp(AX)
MOVL 0(SP), BX // caller's PC
MOVL BX, gobuf_pc(AX)
MOVL $0, gobuf_ret(AX)
MOVL $0, gobuf_ctxt(AX)
get_tls(CX)
MOVL g(CX), BX
MOVL BX, gobuf_g(AX)
RET
// void gogo(Gobuf*)
// restore state from Gobuf; longjmp
TEXT runtime·gogo(SB), NOSPLIT, $0-4
MOVL buf+0(FP), BX // gobuf
MOVL gobuf_g(BX), DX
MOVL 0(DX), CX // make sure g != nil
get_tls(CX)
MOVL DX, g(CX)
MOVL gobuf_sp(BX), SP // restore SP
MOVL gobuf_ret(BX), AX
MOVL gobuf_ctxt(BX), DX
MOVL $0, gobuf_sp(BX) // clear to help garbage collector
MOVL $0, gobuf_ret(BX)
MOVL $0, gobuf_ctxt(BX)
MOVL gobuf_pc(BX), BX
JMP BX
// func mcall(fn func(*g))
// Switch to m->g0's stack, call fn(g).
// Fn must never return. It should gogo(&g->sched)
// to keep running g.
TEXT runtime·mcall(SB), NOSPLIT, $0-4
MOVL fn+0(FP), DI
get_tls(CX)
MOVL g(CX), AX // save state in g->sched
MOVL 0(SP), BX // caller's PC
MOVL BX, (g_sched+gobuf_pc)(AX)
LEAL fn+0(FP), BX // caller's SP
MOVL BX, (g_sched+gobuf_sp)(AX)
MOVL AX, (g_sched+gobuf_g)(AX)
// switch to m->g0 & its stack, call fn
MOVL g(CX), BX
MOVL g_m(BX), BX
MOVL m_g0(BX), SI
CMPL SI, AX // if g == m->g0 call badmcall
JNE 3(PC)
MOVL $runtime·badmcall(SB), AX
JMP AX
MOVL SI, g(CX) // g = m->g0
MOVL (g_sched+gobuf_sp)(SI), SP // sp = m->g0->sched.sp
PUSHL AX
MOVL DI, DX
MOVL 0(DI), DI
CALL DI
POPL AX
MOVL $runtime·badmcall2(SB), AX
JMP AX
RET
// systemstack_switch is a dummy routine that systemstack leaves at the bottom
// of the G stack. We need to distinguish the routine that
// lives at the bottom of the G stack from the one that lives
// at the top of the system stack because the one at the top of
// the system stack terminates the stack walk (see topofstack()).
TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0
RET
// func systemstack(fn func())
TEXT runtime·systemstack(SB), NOSPLIT, $0-4
MOVL fn+0(FP), DI // DI = fn
get_tls(CX)
MOVL g(CX), AX // AX = g
MOVL g_m(AX), BX // BX = m
MOVL m_gsignal(BX), DX // DX = gsignal
CMPL AX, DX
JEQ noswitch
MOVL m_g0(BX), DX // DX = g0
CMPL AX, DX
JEQ noswitch
MOVL m_curg(BX), BP
CMPL AX, BP
JEQ switch
// Bad: g is not gsignal, not g0, not curg. What is it?
// Hide call from linker nosplit analysis.
MOVL $runtime·badsystemstack(SB), AX
CALL AX
switch:
// save our state in g->sched. Pretend to
// be systemstack_switch if the G stack is scanned.
MOVL $runtime·systemstack_switch(SB), (g_sched+gobuf_pc)(AX)
MOVL SP, (g_sched+gobuf_sp)(AX)
MOVL AX, (g_sched+gobuf_g)(AX)
// switch to g0
MOVL DX, g(CX)
MOVL (g_sched+gobuf_sp)(DX), BX
// make it look like mstart called systemstack on g0, to stop traceback
SUBL $4, BX
MOVL $runtime·mstart(SB), DX
MOVL DX, 0(BX)
MOVL BX, SP
// call target function
MOVL DI, DX
MOVL 0(DI), DI
CALL DI
// switch back to g
get_tls(CX)
MOVL g(CX), AX
MOVL g_m(AX), BX
MOVL m_curg(BX), AX
MOVL AX, g(CX)
MOVL (g_sched+gobuf_sp)(AX), SP
MOVL $0, (g_sched+gobuf_sp)(AX)
RET
noswitch:
// already on system stack, just call directly
MOVL DI, DX
MOVL 0(DI), DI
CALL DI
RET
/*
* support for morestack
*/
// Called during function prolog when more stack is needed.
//
// The traceback routines see morestack on a g0 as being
// the top of a stack (for example, morestack calling newstack
// calling the scheduler calling newm calling gc), so we must
// record an argument size. For that purpose, it has no arguments.
TEXT runtime·morestack(SB),NOSPLIT,$0-0
// Cannot grow scheduler stack (m->g0).
get_tls(CX)
MOVL g(CX), BX
MOVL g_m(BX), BX
MOVL m_g0(BX), SI
CMPL g(CX), SI
JNE 2(PC)
INT $3
// Cannot grow signal stack.
MOVL m_gsignal(BX), SI
CMPL g(CX), SI
JNE 2(PC)
INT $3
// Called from f.
// Set m->morebuf to f's caller.
MOVL 4(SP), DI // f's caller's PC
MOVL DI, (m_morebuf+gobuf_pc)(BX)
LEAL 8(SP), CX // f's caller's SP
MOVL CX, (m_morebuf+gobuf_sp)(BX)
get_tls(CX)
MOVL g(CX), SI
MOVL SI, (m_morebuf+gobuf_g)(BX)
// Set g->sched to context in f.
MOVL 0(SP), AX // f's PC
MOVL AX, (g_sched+gobuf_pc)(SI)
MOVL SI, (g_sched+gobuf_g)(SI)
LEAL 4(SP), AX // f's SP
MOVL AX, (g_sched+gobuf_sp)(SI)
MOVL DX, (g_sched+gobuf_ctxt)(SI)
// Call newstack on m->g0's stack.
MOVL m_g0(BX), BP
MOVL BP, g(CX)
MOVL (g_sched+gobuf_sp)(BP), AX
MOVL -4(AX), BX // fault if CALL would, before smashing SP
MOVL AX, SP
CALL runtime·newstack(SB)
MOVL $0, 0x1003 // crash if newstack returns
RET
TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0-0
MOVL $0, DX
JMP runtime·morestack(SB)
// reflectcall: call a function with the given argument list
// func call(argtype *_type, f *FuncVal, arg *byte, argsize, retoffset uint32).
// we don't have variable-sized frames, so we use a small number
// of constant-sized-frame functions to encode a few bits of size in the pc.
// Caution: ugly multiline assembly macros in your future!
#define DISPATCH(NAME,MAXSIZE) \
CMPL CX, $MAXSIZE; \
JA 3(PC); \
MOVL $NAME(SB), AX; \
JMP AX
// Note: can't just "JMP NAME(SB)" - bad inlining results.
TEXT reflect·call(SB), NOSPLIT, $0-0
JMP ·reflectcall(SB)
TEXT ·reflectcall(SB), NOSPLIT, $0-20
MOVL argsize+12(FP), CX
DISPATCH(runtime·call16, 16)
DISPATCH(runtime·call32, 32)
DISPATCH(runtime·call64, 64)
DISPATCH(runtime·call128, 128)
DISPATCH(runtime·call256, 256)
DISPATCH(runtime·call512, 512)
DISPATCH(runtime·call1024, 1024)
DISPATCH(runtime·call2048, 2048)
DISPATCH(runtime·call4096, 4096)
DISPATCH(runtime·call8192, 8192)
DISPATCH(runtime·call16384, 16384)
DISPATCH(runtime·call32768, 32768)
DISPATCH(runtime·call65536, 65536)
DISPATCH(runtime·call131072, 131072)
DISPATCH(runtime·call262144, 262144)
DISPATCH(runtime·call524288, 524288)
DISPATCH(runtime·call1048576, 1048576)
DISPATCH(runtime·call2097152, 2097152)
DISPATCH(runtime·call4194304, 4194304)
DISPATCH(runtime·call8388608, 8388608)
DISPATCH(runtime·call16777216, 16777216)
DISPATCH(runtime·call33554432, 33554432)
DISPATCH(runtime·call67108864, 67108864)
DISPATCH(runtime·call134217728, 134217728)
DISPATCH(runtime·call268435456, 268435456)
DISPATCH(runtime·call536870912, 536870912)
DISPATCH(runtime·call1073741824, 1073741824)
MOVL $runtime·badreflectcall(SB), AX
JMP AX
#define CALLFN(NAME,MAXSIZE) \
TEXT NAME(SB), WRAPPER, $MAXSIZE-20; \
NO_LOCAL_POINTERS; \
/* copy arguments to stack */ \
MOVL argptr+8(FP), SI; \
MOVL argsize+12(FP), CX; \
MOVL SP, DI; \
REP;MOVSB; \
/* call function */ \
MOVL f+4(FP), DX; \
MOVL (DX), AX; \
PCDATA $PCDATA_StackMapIndex, $0; \
CALL AX; \
/* copy return values back */ \
MOVL argptr+8(FP), DI; \
MOVL argsize+12(FP), CX; \
MOVL retoffset+16(FP), BX; \
MOVL SP, SI; \
ADDL BX, DI; \
ADDL BX, SI; \
SUBL BX, CX; \
REP;MOVSB; \
/* execute write barrier updates */ \
MOVL argtype+0(FP), DX; \
MOVL argptr+8(FP), DI; \
MOVL argsize+12(FP), CX; \
MOVL retoffset+16(FP), BX; \
MOVL DX, 0(SP); \
MOVL DI, 4(SP); \
MOVL CX, 8(SP); \
MOVL BX, 12(SP); \
CALL runtime·callwritebarrier(SB); \
RET
CALLFN(·call16, 16)
CALLFN(·call32, 32)
CALLFN(·call64, 64)
CALLFN(·call128, 128)
CALLFN(·call256, 256)
CALLFN(·call512, 512)
CALLFN(·call1024, 1024)
CALLFN(·call2048, 2048)
CALLFN(·call4096, 4096)
CALLFN(·call8192, 8192)
CALLFN(·call16384, 16384)
CALLFN(·call32768, 32768)
CALLFN(·call65536, 65536)
CALLFN(·call131072, 131072)
CALLFN(·call262144, 262144)
CALLFN(·call524288, 524288)
CALLFN(·call1048576, 1048576)
CALLFN(·call2097152, 2097152)
CALLFN(·call4194304, 4194304)
CALLFN(·call8388608, 8388608)
CALLFN(·call16777216, 16777216)
CALLFN(·call33554432, 33554432)
CALLFN(·call67108864, 67108864)
CALLFN(·call134217728, 134217728)
CALLFN(·call268435456, 268435456)
CALLFN(·call536870912, 536870912)
CALLFN(·call1073741824, 1073741824)
// bool cas(int32 *val, int32 old, int32 new)
// Atomically:
// if(*val == old){
// *val = new;
// return 1;
// }else
// return 0;
TEXT runtime·cas(SB), NOSPLIT, $0-13
MOVL ptr+0(FP), BX
MOVL old+4(FP), AX
MOVL new+8(FP), CX
LOCK
CMPXCHGL CX, 0(BX)
SETEQ ret+12(FP)
RET
TEXT runtime·casuintptr(SB), NOSPLIT, $0-13
JMP runtime·cas(SB)
TEXT runtime·atomicloaduintptr(SB), NOSPLIT, $0-8
JMP runtime·atomicload(SB)
TEXT runtime·atomicloaduint(SB), NOSPLIT, $0-8
JMP runtime·atomicload(SB)
TEXT runtime·atomicstoreuintptr(SB), NOSPLIT, $0-8
JMP runtime·atomicstore(SB)
// bool runtime·cas64(uint64 *val, uint64 old, uint64 new)
// Atomically:
// if(*val == *old){
// *val = new;
// return 1;
// } else {
// return 0;
// }
TEXT runtime·cas64(SB), NOSPLIT, $0-21
MOVL ptr+0(FP), BP
MOVL old_lo+4(FP), AX
MOVL old_hi+8(FP), DX
MOVL new_lo+12(FP), BX
MOVL new_hi+16(FP), CX
LOCK
CMPXCHG8B 0(BP)
SETEQ ret+20(FP)
RET
// bool casp(void **p, void *old, void *new)
// Atomically:
// if(*p == old){
// *p = new;
// return 1;
// }else
// return 0;
TEXT runtime·casp1(SB), NOSPLIT, $0-13
MOVL ptr+0(FP), BX
MOVL old+4(FP), AX
MOVL new+8(FP), CX
LOCK
CMPXCHGL CX, 0(BX)
SETEQ ret+12(FP)
RET
// uint32 xadd(uint32 volatile *val, int32 delta)
// Atomically:
// *val += delta;
// return *val;
TEXT runtime·xadd(SB), NOSPLIT, $0-12
MOVL ptr+0(FP), BX
MOVL delta+4(FP), AX
MOVL AX, CX
LOCK
XADDL AX, 0(BX)
ADDL CX, AX
MOVL AX, ret+8(FP)
RET
TEXT runtime·xchg(SB), NOSPLIT, $0-12
MOVL ptr+0(FP), BX
MOVL new+4(FP), AX
XCHGL AX, 0(BX)
MOVL AX, ret+8(FP)
RET
TEXT runtime·xchgp1(SB), NOSPLIT, $0-12
MOVL ptr+0(FP), BX
MOVL new+4(FP), AX
XCHGL AX, 0(BX)
MOVL AX, ret+8(FP)
RET
TEXT runtime·xchguintptr(SB), NOSPLIT, $0-12
JMP runtime·xchg(SB)
TEXT runtime·procyield(SB),NOSPLIT,$0-0
MOVL cycles+0(FP), AX
again:
PAUSE
SUBL $1, AX
JNZ again
RET
TEXT runtime·atomicstorep1(SB), NOSPLIT, $0-8
MOVL ptr+0(FP), BX
MOVL val+4(FP), AX
XCHGL AX, 0(BX)
RET
TEXT runtime·atomicstore(SB), NOSPLIT, $0-8
MOVL ptr+0(FP), BX
MOVL val+4(FP), AX
XCHGL AX, 0(BX)
RET
// uint64 atomicload64(uint64 volatile* addr);
TEXT runtime·atomicload64(SB), NOSPLIT, $0-12
MOVL ptr+0(FP), AX
TESTL $7, AX
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
LEAL ret_lo+4(FP), BX
// MOVQ (%EAX), %MM0
BYTE $0x0f; BYTE $0x6f; BYTE $0x00
// MOVQ %MM0, 0(%EBX)
BYTE $0x0f; BYTE $0x7f; BYTE $0x03
// EMMS
BYTE $0x0F; BYTE $0x77
RET
// void runtime·atomicstore64(uint64 volatile* addr, uint64 v);
TEXT runtime·atomicstore64(SB), NOSPLIT, $0-12
MOVL ptr+0(FP), AX
TESTL $7, AX
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
// MOVQ and EMMS were introduced on the Pentium MMX.
// MOVQ 0x8(%ESP), %MM0
BYTE $0x0f; BYTE $0x6f; BYTE $0x44; BYTE $0x24; BYTE $0x08
// MOVQ %MM0, (%EAX)
BYTE $0x0f; BYTE $0x7f; BYTE $0x00
// EMMS
BYTE $0x0F; BYTE $0x77
// This is essentially a no-op, but it provides required memory fencing.
// It can be replaced with MFENCE, but MFENCE was introduced only on the Pentium4 (SSE2).
MOVL $0, AX
LOCK
XADDL AX, (SP)
RET
// void runtime·atomicor8(byte volatile*, byte);
TEXT runtime·atomicor8(SB), NOSPLIT, $0-5
MOVL ptr+0(FP), AX
MOVB val+4(FP), BX
LOCK
ORB BX, (AX)
RET
// void runtime·atomicand8(byte volatile*, byte);
TEXT runtime·atomicand8(SB), NOSPLIT, $0-5
MOVL ptr+0(FP), AX
MOVB val+4(FP), BX
LOCK
ANDB BX, (AX)
RET
// void jmpdefer(fn, sp);
// called from deferreturn.
// 1. pop the caller
// 2. sub 5 bytes from the callers return
// 3. jmp to the argument
TEXT runtime·jmpdefer(SB), NOSPLIT, $0-8
MOVL fv+0(FP), DX // fn
MOVL argp+4(FP), BX // caller sp
LEAL -4(BX), SP // caller sp after CALL
SUBL $5, (SP) // return to CALL again
MOVL 0(DX), BX
JMP BX // but first run the deferred function
// Save state of caller into g->sched.
TEXT gosave<>(SB),NOSPLIT,$0
PUSHL AX
PUSHL BX
get_tls(BX)
MOVL g(BX), BX
LEAL arg+0(FP), AX
MOVL AX, (g_sched+gobuf_sp)(BX)
MOVL -4(AX), AX
MOVL AX, (g_sched+gobuf_pc)(BX)
MOVL $0, (g_sched+gobuf_ret)(BX)
MOVL $0, (g_sched+gobuf_ctxt)(BX)
POPL BX
POPL AX
RET
// asmcgocall(void(*fn)(void*), void *arg)
// Call fn(arg) on the scheduler stack,
// aligned appropriately for the gcc ABI.
// See cgocall.c for more details.
TEXT ·asmcgocall(SB),NOSPLIT,$0-8
MOVL fn+0(FP), AX
MOVL arg+4(FP), BX
CALL asmcgocall<>(SB)
RET
TEXT ·asmcgocall_errno(SB),NOSPLIT,$0-12
MOVL fn+0(FP), AX
MOVL arg+4(FP), BX
CALL asmcgocall<>(SB)
MOVL AX, ret+8(FP)
RET
TEXT asmcgocall<>(SB),NOSPLIT,$0-0
// fn in AX, arg in BX
MOVL SP, DX
// Figure out if we need to switch to m->g0 stack.
// We get called to create new OS threads too, and those
// come in on the m->g0 stack already.
get_tls(CX)
MOVL g(CX), BP
MOVL g_m(BP), BP
MOVL m_g0(BP), SI
MOVL g(CX), DI
CMPL SI, DI
JEQ 4(PC)
CALL gosave<>(SB)
MOVL SI, g(CX)
MOVL (g_sched+gobuf_sp)(SI), SP
// Now on a scheduling stack (a pthread-created stack).
SUBL $32, SP
ANDL $~15, SP // alignment, perhaps unnecessary
MOVL DI, 8(SP) // save g
MOVL (g_stack+stack_hi)(DI), DI
SUBL DX, DI
MOVL DI, 4(SP) // save depth in stack (can't just save SP, as stack might be copied during a callback)
MOVL BX, 0(SP) // first argument in x86-32 ABI
CALL AX
// Restore registers, g, stack pointer.
get_tls(CX)
MOVL 8(SP), DI
MOVL (g_stack+stack_hi)(DI), SI
SUBL 4(SP), SI
MOVL DI, g(CX)
MOVL SI, SP
RET
// cgocallback(void (*fn)(void*), void *frame, uintptr framesize)
// Turn the fn into a Go func (by taking its address) and call
// cgocallback_gofunc.
TEXT runtime·cgocallback(SB),NOSPLIT,$12-12
LEAL fn+0(FP), AX
MOVL AX, 0(SP)
MOVL frame+4(FP), AX
MOVL AX, 4(SP)
MOVL framesize+8(FP), AX
MOVL AX, 8(SP)
MOVL $runtime·cgocallback_gofunc(SB), AX
CALL AX
RET
// cgocallback_gofunc(FuncVal*, void *frame, uintptr framesize)
// See cgocall.c for more details.
TEXT ·cgocallback_gofunc(SB),NOSPLIT,$12-12
NO_LOCAL_POINTERS
// If g is nil, Go did not create the current thread.
// Call needm to obtain one for temporary use.
// In this case, we're running on the thread stack, so there's
// lots of space, but the linker doesn't know. Hide the call from
// the linker analysis by using an indirect call through AX.
get_tls(CX)
#ifdef GOOS_windows
MOVL $0, BP
CMPL CX, $0
JEQ 2(PC) // TODO
#endif
MOVL g(CX), BP
CMPL BP, $0
JEQ needm
MOVL g_m(BP), BP
MOVL BP, DX // saved copy of oldm
JMP havem
needm:
MOVL $0, 0(SP)
MOVL $runtime·needm(SB), AX
CALL AX
MOVL 0(SP), DX
get_tls(CX)
MOVL g(CX), BP
MOVL g_m(BP), BP
// Set m->sched.sp = SP, so that if a panic happens
// during the function we are about to execute, it will
// have a valid SP to run on the g0 stack.
// The next few lines (after the havem label)
// will save this SP onto the stack and then write
// the same SP back to m->sched.sp. That seems redundant,
// but if an unrecovered panic happens, unwindm will
// restore the g->sched.sp from the stack location
// and then systemstack will try to use it. If we don't set it here,
// that restored SP will be uninitialized (typically 0) and
// will not be usable.
MOVL m_g0(BP), SI
MOVL SP, (g_sched+gobuf_sp)(SI)
havem:
// Now there's a valid m, and we're running on its m->g0.
// Save current m->g0->sched.sp on stack and then set it to SP.
// Save current sp in m->g0->sched.sp in preparation for
// switch back to m->curg stack.
// NOTE: unwindm knows that the saved g->sched.sp is at 0(SP).
MOVL m_g0(BP), SI
MOVL (g_sched+gobuf_sp)(SI), AX
MOVL AX, 0(SP)
MOVL SP, (g_sched+gobuf_sp)(SI)
// Switch to m->curg stack and call runtime.cgocallbackg.
// Because we are taking over the execution of m->curg
// but *not* resuming what had been running, we need to
// save that information (m->curg->sched) so we can restore it.
// We can restore m->curg->sched.sp easily, because calling
// runtime.cgocallbackg leaves SP unchanged upon return.
// To save m->curg->sched.pc, we push it onto the stack.
// This has the added benefit that it looks to the traceback
// routine like cgocallbackg is going to return to that
// PC (because the frame we allocate below has the same
// size as cgocallback_gofunc's frame declared above)
// so that the traceback will seamlessly trace back into
// the earlier calls.
//
// In the new goroutine, 0(SP) holds the saved oldm (DX) register.
// 4(SP) and 8(SP) are unused.
MOVL m_curg(BP), SI
MOVL SI, g(CX)
MOVL (g_sched+gobuf_sp)(SI), DI // prepare stack as DI
MOVL (g_sched+gobuf_pc)(SI), BP
MOVL BP, -4(DI)
LEAL -(4+12)(DI), SP
MOVL DX, 0(SP)
CALL runtime·cgocallbackg(SB)
MOVL 0(SP), DX
// Restore g->sched (== m->curg->sched) from saved values.
get_tls(CX)
MOVL g(CX), SI
MOVL 12(SP), BP
MOVL BP, (g_sched+gobuf_pc)(SI)
LEAL (12+4)(SP), DI
MOVL DI, (g_sched+gobuf_sp)(SI)
// Switch back to m->g0's stack and restore m->g0->sched.sp.
// (Unlike m->curg, the g0 goroutine never uses sched.pc,
// so we do not have to restore it.)
MOVL g(CX), BP
MOVL g_m(BP), BP
MOVL m_g0(BP), SI
MOVL SI, g(CX)
MOVL (g_sched+gobuf_sp)(SI), SP
MOVL 0(SP), AX
MOVL AX, (g_sched+gobuf_sp)(SI)
// If the m on entry was nil, we called needm above to borrow an m
// for the duration of the call. Since the call is over, return it with dropm.
CMPL DX, $0
JNE 3(PC)
MOVL $runtime·dropm(SB), AX
CALL AX
// Done!
RET
// void setg(G*); set g. for use by needm.
TEXT runtime·setg(SB), NOSPLIT, $0-4
MOVL gg+0(FP), BX
#ifdef GOOS_windows
CMPL BX, $0
JNE settls
MOVL $0, 0x14(FS)
RET
settls:
MOVL g_m(BX), AX
LEAL m_tls(AX), AX
MOVL AX, 0x14(FS)
#endif
get_tls(CX)
MOVL BX, g(CX)
RET
// void setg_gcc(G*); set g. for use by gcc
TEXT setg_gcc<>(SB), NOSPLIT, $0
get_tls(AX)
MOVL gg+0(FP), DX
MOVL DX, g(AX)
RET
// check that SP is in range [g->stack.lo, g->stack.hi)
TEXT runtime·stackcheck(SB), NOSPLIT, $0-0
get_tls(CX)
MOVL g(CX), AX
CMPL (g_stack+stack_hi)(AX), SP
JHI 2(PC)
INT $3
CMPL SP, (g_stack+stack_lo)(AX)
JHI 2(PC)
INT $3
RET
TEXT runtime·getcallerpc(SB),NOSPLIT,$0-8
MOVL argp+0(FP),AX // addr of first arg
MOVL -4(AX),AX // get calling pc
MOVL AX, ret+4(FP)
RET
TEXT runtime·setcallerpc(SB),NOSPLIT,$0-8
MOVL argp+0(FP),AX // addr of first arg
MOVL pc+4(FP), BX
MOVL BX, -4(AX) // set calling pc
RET
TEXT runtime·getcallersp(SB), NOSPLIT, $0-8
MOVL argp+0(FP), AX
MOVL AX, ret+4(FP)
RET
// func cputicks() int64
TEXT runtime·cputicks(SB),NOSPLIT,$0-8
TESTL $0x4000000, runtime·cpuid_edx(SB) // no sse2, no mfence
JEQ done
CMPB runtime·lfenceBeforeRdtsc(SB), $1
JNE mfence
BYTE $0x0f; BYTE $0xae; BYTE $0xe8 // LFENCE
JMP done
mfence:
BYTE $0x0f; BYTE $0xae; BYTE $0xf0 // MFENCE
done:
RDTSC
MOVL AX, ret_lo+0(FP)
MOVL DX, ret_hi+4(FP)
RET
TEXT runtime·ldt0setup(SB),NOSPLIT,$16-0
// set up ldt 7 to point at tls0
// ldt 1 would be fine on Linux, but on OS X, 7 is as low as we can go.
// the entry number is just a hint. setldt will set up GS with what it used.
MOVL $7, 0(SP)
LEAL runtime·tls0(SB), AX
MOVL AX, 4(SP)
MOVL $32, 8(SP) // sizeof(tls array)
CALL runtime·setldt(SB)
RET
TEXT runtime·emptyfunc(SB),0,$0-0
RET
TEXT runtime·abort(SB),NOSPLIT,$0-0
INT $0x3
// memhash_varlen(p unsafe.Pointer, h seed) uintptr
// redirects to memhash(p, h, size) using the size
// stored in the closure.
TEXT runtime·memhash_varlen(SB),NOSPLIT,$16-12
GO_ARGS
NO_LOCAL_POINTERS
MOVL p+0(FP), AX
MOVL h+4(FP), BX
MOVL 4(DX), CX
MOVL AX, 0(SP)
MOVL BX, 4(SP)
MOVL CX, 8(SP)
CALL runtime·memhash(SB)
MOVL 12(SP), AX
MOVL AX, ret+8(FP)
RET
// hash function using AES hardware instructions
TEXT runtime·aeshash(SB),NOSPLIT,$0-16
MOVL p+0(FP), AX // ptr to data
MOVL s+8(FP), CX // size
LEAL ret+12(FP), DX
JMP runtime·aeshashbody(SB)
TEXT runtime·aeshashstr(SB),NOSPLIT,$0-12
MOVL p+0(FP), AX // ptr to string object
MOVL 4(AX), CX // length of string
MOVL (AX), AX // string data
LEAL ret+8(FP), DX
JMP runtime·aeshashbody(SB)
// AX: data
// CX: length
// DX: address to put return value
TEXT runtime·aeshashbody(SB),NOSPLIT,$0-0
MOVL h+4(FP), X6 // seed to low 64 bits of xmm6
PINSRD $2, CX, X6 // size to high 64 bits of xmm6
PSHUFHW $0, X6, X6 // replace size with its low 2 bytes repeated 4 times
MOVO runtime·aeskeysched(SB), X7
CMPL CX, $16
JB aes0to15
JE aes16
CMPL CX, $32
JBE aes17to32
CMPL CX, $64
JBE aes33to64
JMP aes65plus
aes0to15:
TESTL CX, CX
JE aes0
ADDL $16, AX
TESTW $0xff0, AX
JE endofpage
// 16 bytes loaded at this address won't cross
// a page boundary, so we can load it directly.
MOVOU -16(AX), X0
ADDL CX, CX
PAND masks<>(SB)(CX*8), X0
// scramble 3 times
AESENC X6, X0
AESENC X7, X0
AESENC X7, X0
MOVL X0, (DX)
RET
endofpage:
// address ends in 1111xxxx. Might be up against
// a page boundary, so load ending at last byte.
// Then shift bytes down using pshufb.
MOVOU -32(AX)(CX*1), X0
ADDL CX, CX
PSHUFB shifts<>(SB)(CX*8), X0
AESENC X6, X0
AESENC X7, X0
AESENC X7, X0
MOVL X0, (DX)
RET
aes0:
// return input seed
MOVL h+4(FP), AX
MOVL AX, (DX)
RET
aes16:
MOVOU (AX), X0
AESENC X6, X0
AESENC X7, X0
AESENC X7, X0
MOVL X0, (DX)
RET
aes17to32:
// load data to be hashed
MOVOU (AX), X0
MOVOU -16(AX)(CX*1), X1
// scramble 3 times
AESENC X6, X0
AESENC runtime·aeskeysched+16(SB), X1
AESENC X7, X0
AESENC X7, X1
AESENC X7, X0
AESENC X7, X1
// combine results
PXOR X1, X0
MOVL X0, (DX)
RET
aes33to64:
MOVOU (AX), X0
MOVOU 16(AX), X1
MOVOU -32(AX)(CX*1), X2
MOVOU -16(AX)(CX*1), X3
AESENC X6, X0
AESENC runtime·aeskeysched+16(SB), X1
AESENC runtime·aeskeysched+32(SB), X2
AESENC runtime·aeskeysched+48(SB), X3
AESENC X7, X0
AESENC X7, X1
AESENC X7, X2
AESENC X7, X3
AESENC X7, X0
AESENC X7, X1
AESENC X7, X2
AESENC X7, X3
PXOR X2, X0
PXOR X3, X1
PXOR X1, X0
MOVL X0, (DX)
RET
aes65plus:
// start with last (possibly overlapping) block
MOVOU -64(AX)(CX*1), X0
MOVOU -48(AX)(CX*1), X1
MOVOU -32(AX)(CX*1), X2
MOVOU -16(AX)(CX*1), X3
// scramble state once
AESENC X6, X0
AESENC runtime·aeskeysched+16(SB), X1
AESENC runtime·aeskeysched+32(SB), X2
AESENC runtime·aeskeysched+48(SB), X3
// compute number of remaining 64-byte blocks
DECL CX
SHRL $6, CX
aesloop:
// scramble state, xor in a block
MOVOU (AX), X4
MOVOU 16(AX), X5
AESENC X4, X0
AESENC X5, X1
MOVOU 32(AX), X4
MOVOU 48(AX), X5
AESENC X4, X2
AESENC X5, X3
// scramble state
AESENC X7, X0
AESENC X7, X1
AESENC X7, X2
AESENC X7, X3
ADDL $64, AX
DECL CX
JNE aesloop
// 2 more scrambles to finish
AESENC X7, X0
AESENC X7, X1
AESENC X7, X2
AESENC X7, X3
AESENC X7, X0
AESENC X7, X1
AESENC X7, X2
AESENC X7, X3
PXOR X2, X0
PXOR X3, X1
PXOR X1, X0
MOVL X0, (DX)
RET
TEXT runtime·aeshash32(SB),NOSPLIT,$0-12
MOVL p+0(FP), AX // ptr to data
MOVL h+4(FP), X0 // seed
PINSRD $1, (AX), X0 // data
AESENC runtime·aeskeysched+0(SB), X0
AESENC runtime·aeskeysched+16(SB), X0
AESENC runtime·aeskeysched+32(SB), X0
MOVL X0, ret+8(FP)
RET
TEXT runtime·aeshash64(SB),NOSPLIT,$0-12
MOVL p+0(FP), AX // ptr to data
MOVQ (AX), X0 // data
PINSRD $2, h+4(FP), X0 // seed
AESENC runtime·aeskeysched+0(SB), X0
AESENC runtime·aeskeysched+16(SB), X0
AESENC runtime·aeskeysched+32(SB), X0
MOVL X0, ret+8(FP)
RET
// simple mask to get rid of data in the high part of the register.
DATA masks<>+0x00(SB)/4, $0x00000000
DATA masks<>+0x04(SB)/4, $0x00000000
DATA masks<>+0x08(SB)/4, $0x00000000
DATA masks<>+0x0c(SB)/4, $0x00000000
DATA masks<>+0x10(SB)/4, $0x000000ff
DATA masks<>+0x14(SB)/4, $0x00000000
DATA masks<>+0x18(SB)/4, $0x00000000
DATA masks<>+0x1c(SB)/4, $0x00000000
DATA masks<>+0x20(SB)/4, $0x0000ffff
DATA masks<>+0x24(SB)/4, $0x00000000
DATA masks<>+0x28(SB)/4, $0x00000000
DATA masks<>+0x2c(SB)/4, $0x00000000
DATA masks<>+0x30(SB)/4, $0x00ffffff
DATA masks<>+0x34(SB)/4, $0x00000000
DATA masks<>+0x38(SB)/4, $0x00000000
DATA masks<>+0x3c(SB)/4, $0x00000000
DATA masks<>+0x40(SB)/4, $0xffffffff
DATA masks<>+0x44(SB)/4, $0x00000000
DATA masks<>+0x48(SB)/4, $0x00000000
DATA masks<>+0x4c(SB)/4, $0x00000000
DATA masks<>+0x50(SB)/4, $0xffffffff
DATA masks<>+0x54(SB)/4, $0x000000ff
DATA masks<>+0x58(SB)/4, $0x00000000
DATA masks<>+0x5c(SB)/4, $0x00000000
DATA masks<>+0x60(SB)/4, $0xffffffff
DATA masks<>+0x64(SB)/4, $0x0000ffff
DATA masks<>+0x68(SB)/4, $0x00000000
DATA masks<>+0x6c(SB)/4, $0x00000000
DATA masks<>+0x70(SB)/4, $0xffffffff
DATA masks<>+0x74(SB)/4, $0x00ffffff
DATA masks<>+0x78(SB)/4, $0x00000000
DATA masks<>+0x7c(SB)/4, $0x00000000
DATA masks<>+0x80(SB)/4, $0xffffffff
DATA masks<>+0x84(SB)/4, $0xffffffff
DATA masks<>+0x88(SB)/4, $0x00000000
DATA masks<>+0x8c(SB)/4, $0x00000000
DATA masks<>+0x90(SB)/4, $0xffffffff
DATA masks<>+0x94(SB)/4, $0xffffffff
DATA masks<>+0x98(SB)/4, $0x000000ff
DATA masks<>+0x9c(SB)/4, $0x00000000
DATA masks<>+0xa0(SB)/4, $0xffffffff
DATA masks<>+0xa4(SB)/4, $0xffffffff
DATA masks<>+0xa8(SB)/4, $0x0000ffff
DATA masks<>+0xac(SB)/4, $0x00000000
DATA masks<>+0xb0(SB)/4, $0xffffffff
DATA masks<>+0xb4(SB)/4, $0xffffffff
DATA masks<>+0xb8(SB)/4, $0x00ffffff
DATA masks<>+0xbc(SB)/4, $0x00000000
DATA masks<>+0xc0(SB)/4, $0xffffffff
DATA masks<>+0xc4(SB)/4, $0xffffffff
DATA masks<>+0xc8(SB)/4, $0xffffffff
DATA masks<>+0xcc(SB)/4, $0x00000000
DATA masks<>+0xd0(SB)/4, $0xffffffff
DATA masks<>+0xd4(SB)/4, $0xffffffff
DATA masks<>+0xd8(SB)/4, $0xffffffff
DATA masks<>+0xdc(SB)/4, $0x000000ff
DATA masks<>+0xe0(SB)/4, $0xffffffff
DATA masks<>+0xe4(SB)/4, $0xffffffff
DATA masks<>+0xe8(SB)/4, $0xffffffff
DATA masks<>+0xec(SB)/4, $0x0000ffff
DATA masks<>+0xf0(SB)/4, $0xffffffff
DATA masks<>+0xf4(SB)/4, $0xffffffff
DATA masks<>+0xf8(SB)/4, $0xffffffff
DATA masks<>+0xfc(SB)/4, $0x00ffffff
GLOBL masks<>(SB),RODATA,$256
// these are arguments to pshufb. They move data down from
// the high bytes of the register to the low bytes of the register.
// index is how many bytes to move.
DATA shifts<>+0x00(SB)/4, $0x00000000
DATA shifts<>+0x04(SB)/4, $0x00000000
DATA shifts<>+0x08(SB)/4, $0x00000000
DATA shifts<>+0x0c(SB)/4, $0x00000000
DATA shifts<>+0x10(SB)/4, $0xffffff0f
DATA shifts<>+0x14(SB)/4, $0xffffffff
DATA shifts<>+0x18(SB)/4, $0xffffffff
DATA shifts<>+0x1c(SB)/4, $0xffffffff
DATA shifts<>+0x20(SB)/4, $0xffff0f0e
DATA shifts<>+0x24(SB)/4, $0xffffffff
DATA shifts<>+0x28(SB)/4, $0xffffffff
DATA shifts<>+0x2c(SB)/4, $0xffffffff
DATA shifts<>+0x30(SB)/4, $0xff0f0e0d
DATA shifts<>+0x34(SB)/4, $0xffffffff
DATA shifts<>+0x38(SB)/4, $0xffffffff
DATA shifts<>+0x3c(SB)/4, $0xffffffff
DATA shifts<>+0x40(SB)/4, $0x0f0e0d0c
DATA shifts<>+0x44(SB)/4, $0xffffffff
DATA shifts<>+0x48(SB)/4, $0xffffffff
DATA shifts<>+0x4c(SB)/4, $0xffffffff
DATA shifts<>+0x50(SB)/4, $0x0e0d0c0b
DATA shifts<>+0x54(SB)/4, $0xffffff0f
DATA shifts<>+0x58(SB)/4, $0xffffffff
DATA shifts<>+0x5c(SB)/4, $0xffffffff
DATA shifts<>+0x60(SB)/4, $0x0d0c0b0a
DATA shifts<>+0x64(SB)/4, $0xffff0f0e
DATA shifts<>+0x68(SB)/4, $0xffffffff
DATA shifts<>+0x6c(SB)/4, $0xffffffff
DATA shifts<>+0x70(SB)/4, $0x0c0b0a09
DATA shifts<>+0x74(SB)/4, $0xff0f0e0d
DATA shifts<>+0x78(SB)/4, $0xffffffff
DATA shifts<>+0x7c(SB)/4, $0xffffffff
DATA shifts<>+0x80(SB)/4, $0x0b0a0908
DATA shifts<>+0x84(SB)/4, $0x0f0e0d0c
DATA shifts<>+0x88(SB)/4, $0xffffffff
DATA shifts<>+0x8c(SB)/4, $0xffffffff
DATA shifts<>+0x90(SB)/4, $0x0a090807
DATA shifts<>+0x94(SB)/4, $0x0e0d0c0b
DATA shifts<>+0x98(SB)/4, $0xffffff0f
DATA shifts<>+0x9c(SB)/4, $0xffffffff
DATA shifts<>+0xa0(SB)/4, $0x09080706
DATA shifts<>+0xa4(SB)/4, $0x0d0c0b0a
DATA shifts<>+0xa8(SB)/4, $0xffff0f0e
DATA shifts<>+0xac(SB)/4, $0xffffffff
DATA shifts<>+0xb0(SB)/4, $0x08070605
DATA shifts<>+0xb4(SB)/4, $0x0c0b0a09
DATA shifts<>+0xb8(SB)/4, $0xff0f0e0d
DATA shifts<>+0xbc(SB)/4, $0xffffffff
DATA shifts<>+0xc0(SB)/4, $0x07060504
DATA shifts<>+0xc4(SB)/4, $0x0b0a0908
DATA shifts<>+0xc8(SB)/4, $0x0f0e0d0c
DATA shifts<>+0xcc(SB)/4, $0xffffffff
DATA shifts<>+0xd0(SB)/4, $0x06050403
DATA shifts<>+0xd4(SB)/4, $0x0a090807
DATA shifts<>+0xd8(SB)/4, $0x0e0d0c0b
DATA shifts<>+0xdc(SB)/4, $0xffffff0f
DATA shifts<>+0xe0(SB)/4, $0x05040302
DATA shifts<>+0xe4(SB)/4, $0x09080706
DATA shifts<>+0xe8(SB)/4, $0x0d0c0b0a
DATA shifts<>+0xec(SB)/4, $0xffff0f0e
DATA shifts<>+0xf0(SB)/4, $0x04030201
DATA shifts<>+0xf4(SB)/4, $0x08070605
DATA shifts<>+0xf8(SB)/4, $0x0c0b0a09
DATA shifts<>+0xfc(SB)/4, $0xff0f0e0d
GLOBL shifts<>(SB),RODATA,$256
TEXT runtime·memeq(SB),NOSPLIT,$0-13
MOVL a+0(FP), SI
MOVL b+4(FP), DI
MOVL size+8(FP), BX
LEAL ret+12(FP), AX
JMP runtime·memeqbody(SB)
// memequal_varlen(a, b unsafe.Pointer) bool
TEXT runtime·memequal_varlen(SB),NOSPLIT,$0-9
MOVL a+0(FP), SI
MOVL b+4(FP), DI
CMPL SI, DI
JEQ eq
MOVL 4(DX), BX // compiler stores size at offset 4 in the closure
LEAL ret+8(FP), AX
JMP runtime·memeqbody(SB)
eq:
MOVB $1, ret+8(FP)
RET
// eqstring tests whether two strings are equal.
// The compiler guarantees that strings passed
// to eqstring have equal length.
// See runtime_test.go:eqstring_generic for
// equivalent Go code.
TEXT runtime·eqstring(SB),NOSPLIT,$0-17
MOVL s1str+0(FP), SI
MOVL s2str+8(FP), DI
CMPL SI, DI
JEQ same
MOVL s1len+4(FP), BX
LEAL v+16(FP), AX
JMP runtime·memeqbody(SB)
same:
MOVB $1, v+16(FP)
RET
TEXT bytes·Equal(SB),NOSPLIT,$0-25
MOVL a_len+4(FP), BX
MOVL b_len+16(FP), CX
CMPL BX, CX
JNE eqret
MOVL a+0(FP), SI
MOVL b+12(FP), DI
LEAL ret+24(FP), AX
JMP runtime·memeqbody(SB)
eqret:
MOVB $0, ret+24(FP)
RET
// a in SI
// b in DI
// count in BX
// address of result byte in AX
TEXT runtime·memeqbody(SB),NOSPLIT,$0-0
CMPL BX, $4
JB small
// 64 bytes at a time using xmm registers
hugeloop:
CMPL BX, $64
JB bigloop
TESTL $0x4000000, runtime·cpuid_edx(SB) // check for sse2
JE bigloop
MOVOU (SI), X0
MOVOU (DI), X1
MOVOU 16(SI), X2
MOVOU 16(DI), X3
MOVOU 32(SI), X4
MOVOU 32(DI), X5
MOVOU 48(SI), X6
MOVOU 48(DI), X7
PCMPEQB X1, X0
PCMPEQB X3, X2
PCMPEQB X5, X4
PCMPEQB X7, X6
PAND X2, X0
PAND X6, X4
PAND X4, X0
PMOVMSKB X0, DX
ADDL $64, SI
ADDL $64, DI
SUBL $64, BX
CMPL DX, $0xffff
JEQ hugeloop
MOVB $0, (AX)
RET
// 4 bytes at a time using 32-bit register
bigloop:
CMPL BX, $4
JBE leftover
MOVL (SI), CX
MOVL (DI), DX
ADDL $4, SI
ADDL $4, DI
SUBL $4, BX
CMPL CX, DX
JEQ bigloop
MOVB $0, (AX)
RET
// remaining 0-4 bytes
leftover:
MOVL -4(SI)(BX*1), CX
MOVL -4(DI)(BX*1), DX
CMPL CX, DX
SETEQ (AX)
RET
small:
CMPL BX, $0
JEQ equal
LEAL 0(BX*8), CX
NEGL CX
MOVL SI, DX
CMPB DX, $0xfc
JA si_high
// load at SI won't cross a page boundary.
MOVL (SI), SI
JMP si_finish
si_high:
// address ends in 111111xx. Load up to bytes we want, move to correct position.
MOVL -4(SI)(BX*1), SI
SHRL CX, SI
si_finish:
// same for DI.
MOVL DI, DX
CMPB DX, $0xfc
JA di_high
MOVL (DI), DI
JMP di_finish
di_high:
MOVL -4(DI)(BX*1), DI
SHRL CX, DI
di_finish:
SUBL SI, DI
SHLL CX, DI
equal:
SETEQ (AX)
RET
TEXT runtime·cmpstring(SB),NOSPLIT,$0-20
MOVL s1_base+0(FP), SI
MOVL s1_len+4(FP), BX
MOVL s2_base+8(FP), DI
MOVL s2_len+12(FP), DX
LEAL ret+16(FP), AX
JMP runtime·cmpbody(SB)
TEXT bytes·Compare(SB),NOSPLIT,$0-28
MOVL s1+0(FP), SI
MOVL s1+4(FP), BX
MOVL s2+12(FP), DI
MOVL s2+16(FP), DX
LEAL ret+24(FP), AX
JMP runtime·cmpbody(SB)
TEXT bytes·IndexByte(SB),NOSPLIT,$0-20
MOVL s+0(FP), SI
MOVL s_len+4(FP), CX
MOVB c+12(FP), AL
MOVL SI, DI
CLD; REPN; SCASB
JZ 3(PC)
MOVL $-1, ret+16(FP)
RET
SUBL SI, DI
SUBL $1, DI
MOVL DI, ret+16(FP)
RET
TEXT strings·IndexByte(SB),NOSPLIT,$0-16
MOVL s+0(FP), SI
MOVL s_len+4(FP), CX
MOVB c+8(FP), AL
MOVL SI, DI
CLD; REPN; SCASB
JZ 3(PC)
MOVL $-1, ret+12(FP)
RET
SUBL SI, DI
SUBL $1, DI
MOVL DI, ret+12(FP)
RET
// input:
// SI = a
// DI = b
// BX = alen
// DX = blen
// AX = address of return word (set to 1/0/-1)
TEXT runtime·cmpbody(SB),NOSPLIT,$0-0
MOVL DX, BP
SUBL BX, DX // DX = blen-alen
CMOVLGT BX, BP // BP = min(alen, blen)
CMPL SI, DI
JEQ allsame
CMPL BP, $4
JB small
TESTL $0x4000000, runtime·cpuid_edx(SB) // check for sse2
JE mediumloop
largeloop:
CMPL BP, $16
JB mediumloop
MOVOU (SI), X0
MOVOU (DI), X1
PCMPEQB X0, X1
PMOVMSKB X1, BX
XORL $0xffff, BX // convert EQ to NE
JNE diff16 // branch if at least one byte is not equal
ADDL $16, SI
ADDL $16, DI
SUBL $16, BP
JMP largeloop
diff16:
BSFL BX, BX // index of first byte that differs
XORL DX, DX
MOVB (SI)(BX*1), CX
CMPB CX, (DI)(BX*1)
SETHI DX
LEAL -1(DX*2), DX // convert 1/0 to +1/-1
MOVL DX, (AX)
RET
mediumloop:
CMPL BP, $4
JBE _0through4
MOVL (SI), BX
MOVL (DI), CX
CMPL BX, CX
JNE diff4
ADDL $4, SI
ADDL $4, DI
SUBL $4, BP
JMP mediumloop
_0through4:
MOVL -4(SI)(BP*1), BX
MOVL -4(DI)(BP*1), CX
CMPL BX, CX
JEQ allsame
diff4:
BSWAPL BX // reverse order of bytes
BSWAPL CX
XORL BX, CX // find bit differences
BSRL CX, CX // index of highest bit difference
SHRL CX, BX // move a's bit to bottom
ANDL $1, BX // mask bit
LEAL -1(BX*2), BX // 1/0 => +1/-1
MOVL BX, (AX)
RET
// 0-3 bytes in common
small:
LEAL (BP*8), CX
NEGL CX
JEQ allsame
// load si
CMPB SI, $0xfc
JA si_high
MOVL (SI), SI
JMP si_finish
si_high:
MOVL -4(SI)(BP*1), SI
SHRL CX, SI
si_finish:
SHLL CX, SI
// same for di
CMPB DI, $0xfc
JA di_high
MOVL (DI), DI
JMP di_finish
di_high:
MOVL -4(DI)(BP*1), DI
SHRL CX, DI
di_finish:
SHLL CX, DI
BSWAPL SI // reverse order of bytes
BSWAPL DI
XORL SI, DI // find bit differences
JEQ allsame
BSRL DI, CX // index of highest bit difference
SHRL CX, SI // move a's bit to bottom
ANDL $1, SI // mask bit
LEAL -1(SI*2), BX // 1/0 => +1/-1
MOVL BX, (AX)
RET
// all the bytes in common are the same, so we just need
// to compare the lengths.
allsame:
XORL BX, BX
XORL CX, CX
TESTL DX, DX
SETLT BX // 1 if alen > blen
SETEQ CX // 1 if alen == blen
LEAL -1(CX)(BX*2), BX // 1,0,-1 result
MOVL BX, (AX)
RET
TEXT runtime·fastrand1(SB), NOSPLIT, $0-4
get_tls(CX)
MOVL g(CX), AX
MOVL g_m(AX), AX
MOVL m_fastrand(AX), DX
ADDL DX, DX
MOVL DX, BX
XORL $0x88888eef, DX
CMOVLMI BX, DX
MOVL DX, m_fastrand(AX)
MOVL DX, ret+0(FP)
RET
TEXT runtime·return0(SB), NOSPLIT, $0
MOVL $0, AX
RET
// Called from cgo wrappers, this function returns g->m->curg.stack.hi.
// Must obey the gcc calling convention.
TEXT _cgo_topofstack(SB),NOSPLIT,$0
get_tls(CX)
MOVL g(CX), AX
MOVL g_m(AX), AX
MOVL m_curg(AX), AX
MOVL (g_stack+stack_hi)(AX), AX
RET
// The top-most function running on a goroutine
// returns to goexit+PCQuantum.
TEXT runtime·goexit(SB),NOSPLIT,$0-0
BYTE $0x90 // NOP
CALL runtime·goexit1(SB) // does not return
// traceback from goexit1 must hit code range of goexit
BYTE $0x90 // NOP
TEXT runtime·prefetcht0(SB),NOSPLIT,$0-4
MOVL addr+0(FP), AX
PREFETCHT0 (AX)
RET
TEXT runtime·prefetcht1(SB),NOSPLIT,$0-4
MOVL addr+0(FP), AX
PREFETCHT1 (AX)
RET
TEXT runtime·prefetcht2(SB),NOSPLIT,$0-4
MOVL addr+0(FP), AX
PREFETCHT2 (AX)
RET
TEXT runtime·prefetchnta(SB),NOSPLIT,$0-4
MOVL addr+0(FP), AX
PREFETCHNTA (AX)
RET