/
asm_amd64.s
2030 lines (1837 loc) · 44 KB
/
asm_amd64.s
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// 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
MOVQ DI, AX // argc
MOVQ SI, BX // argv
SUBQ $(4*8+7), SP // 2args 2auto
ANDQ $~15, SP
MOVQ AX, 16(SP)
MOVQ BX, 24(SP)
// create istack out of the given (operating system) stack.
// _cgo_init may update stackguard.
MOVQ $runtime·g0(SB), DI
LEAQ (-64*1024+104)(SP), BX
MOVQ BX, g_stackguard0(DI)
MOVQ BX, g_stackguard1(DI)
MOVQ BX, (g_stack+stack_lo)(DI)
MOVQ SP, (g_stack+stack_hi)(DI)
// find out information about the processor we're on
MOVQ $0, AX
CPUID
CMPQ 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:
// Do nothing.
MOVQ $1, AX
CPUID
MOVL CX, runtime·cpuid_ecx(SB)
MOVL DX, runtime·cpuid_edx(SB)
// Detect AVX and AVX2 as per 14.7.1 Detection of AVX2 chapter of [1]
// [1] 64-ia-32-architectures-software-developer-manual-325462.pdf
// http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-manual-325462.pdf
ANDL $0x18000000, CX // check for OSXSAVE and AVX bits
CMPL CX, $0x18000000
JNE noavx
MOVL $0, CX
// For XGETBV, OSXSAVE bit is required and sufficient
XGETBV
ANDL $6, AX
CMPL AX, $6 // Check for OS support of YMM registers
JNE noavx
MOVB $1, runtime·support_avx(SB)
MOVL $7, AX
MOVL $0, CX
CPUID
ANDL $0x20, BX // check for AVX2 bit
CMPL BX, $0x20
JNE noavx2
MOVB $1, runtime·support_avx2(SB)
JMP nocpuinfo
noavx:
MOVB $0, runtime·support_avx(SB)
noavx2:
MOVB $0, runtime·support_avx2(SB)
nocpuinfo:
// if there is an _cgo_init, call it.
MOVQ _cgo_init(SB), AX
TESTQ AX, AX
JZ needtls
// g0 already in DI
MOVQ DI, CX // Win64 uses CX for first parameter
MOVQ $setg_gcc<>(SB), SI
CALL AX
// update stackguard after _cgo_init
MOVQ $runtime·g0(SB), CX
MOVQ (g_stack+stack_lo)(CX), AX
ADDQ $const__StackGuard, AX
MOVQ AX, g_stackguard0(CX)
MOVQ AX, g_stackguard1(CX)
#ifndef GOOS_windows
JMP ok
#endif
needtls:
#ifdef GOOS_plan9
// skip TLS setup on Plan 9
JMP ok
#endif
#ifdef GOOS_solaris
// skip TLS setup on Solaris
JMP ok
#endif
LEAQ runtime·m0+m_tls(SB), DI
CALL runtime·settls(SB)
// store through it, to make sure it works
get_tls(BX)
MOVQ $0x123, g(BX)
MOVQ runtime·m0+m_tls(SB), AX
CMPQ AX, $0x123
JEQ 2(PC)
MOVL AX, 0 // abort
ok:
// set the per-goroutine and per-mach "registers"
get_tls(BX)
LEAQ runtime·g0(SB), CX
MOVQ CX, g(BX)
LEAQ runtime·m0(SB), AX
// save m->g0 = g0
MOVQ CX, m_g0(AX)
// save m0 to g0->m
MOVQ AX, g_m(CX)
CLD // convention is D is always left cleared
CALL runtime·check(SB)
MOVL 16(SP), AX // copy argc
MOVL AX, 0(SP)
MOVQ 24(SP), AX // copy argv
MOVQ AX, 8(SP)
CALL runtime·args(SB)
CALL runtime·osinit(SB)
CALL runtime·schedinit(SB)
// create a new goroutine to start program
MOVQ $runtime·mainPC(SB), AX // entry
PUSHQ AX
PUSHQ $0 // arg size
CALL runtime·newproc(SB)
POPQ AX
POPQ AX
// start this M
CALL runtime·mstart(SB)
MOVL $0xf1, 0xf1 // crash
RET
DATA runtime·mainPC+0(SB)/8,$runtime·main(SB)
GLOBL runtime·mainPC(SB),RODATA,$8
TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
BYTE $0xcc
RET
TEXT runtime·asminit(SB),NOSPLIT,$0-0
// No per-thread init.
RET
/*
* go-routine
*/
// void gosave(Gobuf*)
// save state in Gobuf; setjmp
TEXT runtime·gosave(SB), NOSPLIT, $0-8
MOVQ buf+0(FP), AX // gobuf
LEAQ buf+0(FP), BX // caller's SP
MOVQ BX, gobuf_sp(AX)
MOVQ 0(SP), BX // caller's PC
MOVQ BX, gobuf_pc(AX)
MOVQ $0, gobuf_ret(AX)
MOVQ $0, gobuf_ctxt(AX)
MOVQ BP, gobuf_bp(AX)
get_tls(CX)
MOVQ g(CX), BX
MOVQ BX, gobuf_g(AX)
RET
// void gogo(Gobuf*)
// restore state from Gobuf; longjmp
TEXT runtime·gogo(SB), NOSPLIT, $0-8
MOVQ buf+0(FP), BX // gobuf
MOVQ gobuf_g(BX), DX
MOVQ 0(DX), CX // make sure g != nil
get_tls(CX)
MOVQ DX, g(CX)
MOVQ gobuf_sp(BX), SP // restore SP
MOVQ gobuf_ret(BX), AX
MOVQ gobuf_ctxt(BX), DX
MOVQ gobuf_bp(BX), BP
MOVQ $0, gobuf_sp(BX) // clear to help garbage collector
MOVQ $0, gobuf_ret(BX)
MOVQ $0, gobuf_ctxt(BX)
MOVQ $0, gobuf_bp(BX)
MOVQ 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, $0-8
MOVQ fn+0(FP), DI
get_tls(CX)
MOVQ g(CX), AX // save state in g->sched
MOVQ 0(SP), BX // caller's PC
MOVQ BX, (g_sched+gobuf_pc)(AX)
LEAQ fn+0(FP), BX // caller's SP
MOVQ BX, (g_sched+gobuf_sp)(AX)
MOVQ AX, (g_sched+gobuf_g)(AX)
MOVQ BP, (g_sched+gobuf_bp)(AX)
// switch to m->g0 & its stack, call fn
MOVQ g(CX), BX
MOVQ g_m(BX), BX
MOVQ m_g0(BX), SI
CMPQ SI, AX // if g == m->g0 call badmcall
JNE 3(PC)
MOVQ $runtime·badmcall(SB), AX
JMP AX
MOVQ SI, g(CX) // g = m->g0
MOVQ (g_sched+gobuf_sp)(SI), SP // sp = m->g0->sched.sp
PUSHQ AX
MOVQ DI, DX
MOVQ 0(DI), DI
CALL DI
POPQ AX
MOVQ $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, $0-8
MOVQ fn+0(FP), DI // DI = fn
get_tls(CX)
MOVQ g(CX), AX // AX = g
MOVQ g_m(AX), BX // BX = m
MOVQ m_gsignal(BX), DX // DX = gsignal
CMPQ AX, DX
JEQ noswitch
MOVQ m_g0(BX), DX // DX = g0
CMPQ AX, DX
JEQ noswitch
MOVQ m_curg(BX), R8
CMPQ AX, R8
JEQ switch
// Bad: g is not gsignal, not g0, not curg. What is it?
MOVQ $runtime·badsystemstack(SB), AX
CALL AX
switch:
// save our state in g->sched. Pretend to
// be systemstack_switch if the G stack is scanned.
MOVQ $runtime·systemstack_switch(SB), SI
MOVQ SI, (g_sched+gobuf_pc)(AX)
MOVQ SP, (g_sched+gobuf_sp)(AX)
MOVQ AX, (g_sched+gobuf_g)(AX)
MOVQ BP, (g_sched+gobuf_bp)(AX)
// switch to g0
MOVQ DX, g(CX)
MOVQ (g_sched+gobuf_sp)(DX), BX
// make it look like mstart called systemstack on g0, to stop traceback
SUBQ $8, BX
MOVQ $runtime·mstart(SB), DX
MOVQ DX, 0(BX)
MOVQ BX, SP
// call target function
MOVQ DI, DX
MOVQ 0(DI), DI
CALL DI
// switch back to g
get_tls(CX)
MOVQ g(CX), AX
MOVQ g_m(AX), BX
MOVQ m_curg(BX), AX
MOVQ AX, g(CX)
MOVQ (g_sched+gobuf_sp)(AX), SP
MOVQ $0, (g_sched+gobuf_sp)(AX)
RET
noswitch:
// already on m stack, just call directly
MOVQ DI, DX
MOVQ 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)
MOVQ g(CX), BX
MOVQ g_m(BX), BX
MOVQ m_g0(BX), SI
CMPQ g(CX), SI
JNE 2(PC)
INT $3
// Cannot grow signal stack (m->gsignal).
MOVQ m_gsignal(BX), SI
CMPQ g(CX), SI
JNE 2(PC)
INT $3
// Called from f.
// Set m->morebuf to f's caller.
MOVQ 8(SP), AX // f's caller's PC
MOVQ AX, (m_morebuf+gobuf_pc)(BX)
LEAQ 16(SP), AX // f's caller's SP
MOVQ AX, (m_morebuf+gobuf_sp)(BX)
get_tls(CX)
MOVQ g(CX), SI
MOVQ SI, (m_morebuf+gobuf_g)(BX)
// Set g->sched to context in f.
MOVQ 0(SP), AX // f's PC
MOVQ AX, (g_sched+gobuf_pc)(SI)
MOVQ SI, (g_sched+gobuf_g)(SI)
LEAQ 8(SP), AX // f's SP
MOVQ AX, (g_sched+gobuf_sp)(SI)
MOVQ DX, (g_sched+gobuf_ctxt)(SI)
MOVQ BP, (g_sched+gobuf_bp)(SI)
// Call newstack on m->g0's stack.
MOVQ m_g0(BX), BX
MOVQ BX, g(CX)
MOVQ (g_sched+gobuf_sp)(BX), SP
CALL runtime·newstack(SB)
MOVQ $0, 0x1003 // crash if newstack returns
RET
// morestack but not preserving ctxt.
TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0
MOVL $0, DX
JMP runtime·morestack(SB)
TEXT runtime·stackBarrier(SB),NOSPLIT,$0
// We came here via a RET to an overwritten return PC.
// AX may be live. Other registers are available.
// Get the original return PC, g.stkbar[g.stkbarPos].savedLRVal.
get_tls(CX)
MOVQ g(CX), CX
MOVQ (g_stkbar+slice_array)(CX), DX
MOVQ g_stkbarPos(CX), BX
IMULQ $stkbar__size, BX // Too big for SIB.
MOVQ stkbar_savedLRPtr(DX)(BX*1), R8
MOVQ stkbar_savedLRVal(DX)(BX*1), BX
// Assert that we're popping the right saved LR.
ADDQ $8, R8
CMPQ R8, SP
JEQ 2(PC)
MOVL $0, 0
// Record that this stack barrier was hit.
ADDQ $1, g_stkbarPos(CX)
// Jump to the original return PC.
JMP BX
// 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) \
CMPQ CX, $MAXSIZE; \
JA 3(PC); \
MOVQ $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, $0-32
MOVLQZX argsize+24(FP), CX
// NOTE(rsc): No call16, because CALLFN needs four words
// of argument space to invoke callwritebarrier.
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)
MOVQ $runtime·badreflectcall(SB), AX
JMP AX
#define CALLFN(NAME,MAXSIZE) \
TEXT NAME(SB), WRAPPER, $MAXSIZE-32; \
NO_LOCAL_POINTERS; \
/* copy arguments to stack */ \
MOVQ argptr+16(FP), SI; \
MOVLQZX argsize+24(FP), CX; \
MOVQ SP, DI; \
REP;MOVSB; \
/* call function */ \
MOVQ f+8(FP), DX; \
PCDATA $PCDATA_StackMapIndex, $0; \
CALL (DX); \
/* copy return values back */ \
MOVQ argptr+16(FP), DI; \
MOVLQZX argsize+24(FP), CX; \
MOVLQZX retoffset+28(FP), BX; \
MOVQ SP, SI; \
ADDQ BX, DI; \
ADDQ BX, SI; \
SUBQ BX, CX; \
REP;MOVSB; \
/* execute write barrier updates */ \
MOVQ argtype+0(FP), DX; \
MOVQ argptr+16(FP), DI; \
MOVLQZX argsize+24(FP), CX; \
MOVLQZX retoffset+28(FP), BX; \
MOVQ DX, 0(SP); \
MOVQ DI, 8(SP); \
MOVQ CX, 16(SP); \
MOVQ BX, 24(SP); \
CALL runtime·callwritebarrier(SB); \
RET
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)
TEXT runtime·procyield(SB),NOSPLIT,$0-0
MOVL cycles+0(FP), AX
again:
PAUSE
SUBL $1, AX
JNZ again
RET
TEXT ·publicationBarrier(SB),NOSPLIT,$0-0
// Stores are already ordered on x86, so this is just a
// compile barrier.
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, $0-16
MOVQ fv+0(FP), DX // fn
MOVQ argp+8(FP), BX // caller sp
LEAQ -8(BX), SP // caller sp after CALL
SUBQ $5, (SP) // return to CALL again
MOVQ 0(DX), BX
JMP BX // but first run the deferred function
// Save state of caller into g->sched. Smashes R8, R9.
TEXT gosave<>(SB),NOSPLIT,$0
get_tls(R8)
MOVQ g(R8), R8
MOVQ 0(SP), R9
MOVQ R9, (g_sched+gobuf_pc)(R8)
LEAQ 8(SP), R9
MOVQ R9, (g_sched+gobuf_sp)(R8)
MOVQ $0, (g_sched+gobuf_ret)(R8)
MOVQ $0, (g_sched+gobuf_ctxt)(R8)
MOVQ BP, (g_sched+gobuf_bp)(R8)
RET
// func asmcgocall(fn, arg unsafe.Pointer) int32
// Call fn(arg) on the scheduler stack,
// aligned appropriately for the gcc ABI.
// See cgocall.go for more details.
TEXT ·asmcgocall(SB),NOSPLIT,$0-20
MOVQ fn+0(FP), AX
MOVQ arg+8(FP), BX
MOVQ 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)
MOVQ g(CX), R8
CMPQ R8, $0
JEQ nosave
MOVQ g_m(R8), R8
MOVQ m_g0(R8), SI
MOVQ g(CX), DI
CMPQ SI, DI
JEQ nosave
MOVQ m_gsignal(R8), SI
CMPQ SI, DI
JEQ nosave
// Switch to system stack.
MOVQ m_g0(R8), SI
CALL gosave<>(SB)
MOVQ SI, g(CX)
MOVQ (g_sched+gobuf_sp)(SI), SP
// Now on a scheduling stack (a pthread-created stack).
// Make sure we have enough room for 4 stack-backed fast-call
// registers as per windows amd64 calling convention.
SUBQ $64, SP
ANDQ $~15, SP // alignment for gcc ABI
MOVQ DI, 48(SP) // save g
MOVQ (g_stack+stack_hi)(DI), DI
SUBQ DX, DI
MOVQ DI, 40(SP) // save depth in stack (can't just save SP, as stack might be copied during a callback)
MOVQ BX, DI // DI = first argument in AMD64 ABI
MOVQ BX, CX // CX = first argument in Win64
CALL AX
// Restore registers, g, stack pointer.
get_tls(CX)
MOVQ 48(SP), DI
MOVQ (g_stack+stack_hi)(DI), SI
SUBQ 40(SP), SI
MOVQ DI, g(CX)
MOVQ SI, SP
MOVL AX, ret+16(FP)
RET
nosave:
// Running on a system stack, perhaps even without a g.
// Having no g can happen during thread creation or thread teardown
// (see needm/dropm on Solaris, for example).
// This code is like the above sequence but without saving/restoring g
// and without worrying about the stack moving out from under us
// (because we're on a system stack, not a goroutine stack).
// The above code could be used directly if already on a system stack,
// but then the only path through this code would be a rare case on Solaris.
// Using this code for all "already on system stack" calls exercises it more,
// which should help keep it correct.
SUBQ $64, SP
ANDQ $~15, SP
MOVQ $0, 48(SP) // where above code stores g, in case someone looks during debugging
MOVQ DX, 40(SP) // save original stack pointer
MOVQ BX, DI // DI = first argument in AMD64 ABI
MOVQ BX, CX // CX = first argument in Win64
CALL AX
MOVQ 40(SP), SI // restore original stack pointer
MOVQ SI, SP
MOVL AX, ret+16(FP)
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,$24-24
LEAQ fn+0(FP), AX
MOVQ AX, 0(SP)
MOVQ frame+8(FP), AX
MOVQ AX, 8(SP)
MOVQ framesize+16(FP), AX
MOVQ AX, 16(SP)
MOVQ $runtime·cgocallback_gofunc(SB), AX
CALL AX
RET
// cgocallback_gofunc(FuncVal*, void *frame, uintptr framesize)
// See cgocall.go for more details.
TEXT ·cgocallback_gofunc(SB),NOSPLIT,$8-24
NO_LOCAL_POINTERS
// If g is nil, Go did not create the current thread.
// Call needm to obtain one m 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, BX
CMPQ CX, $0
JEQ 2(PC)
#endif
MOVQ g(CX), BX
CMPQ BX, $0
JEQ needm
MOVQ g_m(BX), BX
MOVQ BX, R8 // holds oldm until end of function
JMP havem
needm:
MOVQ $0, 0(SP)
MOVQ $runtime·needm(SB), AX
CALL AX
MOVQ 0(SP), R8
get_tls(CX)
MOVQ g(CX), BX
MOVQ g_m(BX), BX
// 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.
MOVQ m_g0(BX), SI
MOVQ 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).
MOVQ m_g0(BX), SI
MOVQ (g_sched+gobuf_sp)(SI), AX
MOVQ AX, 0(SP)
MOVQ 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 R8.
MOVQ m_curg(BX), SI
MOVQ SI, g(CX)
MOVQ (g_sched+gobuf_sp)(SI), DI // prepare stack as DI
MOVQ (g_sched+gobuf_pc)(SI), BX
MOVQ BX, -8(DI)
// Compute the size of the frame, including return PC and, if
// GOEXPERIMENT=framepointer, the saved based pointer
LEAQ fv+0(FP), AX
SUBQ SP, AX
SUBQ AX, DI
MOVQ DI, SP
MOVQ R8, 0(SP)
CALL runtime·cgocallbackg(SB)
MOVQ 0(SP), R8
// Compute the size of the frame again. FP and SP have
// completely different values here than they did above,
// but only their difference matters.
LEAQ fv+0(FP), AX
SUBQ SP, AX
// Restore g->sched (== m->curg->sched) from saved values.
get_tls(CX)
MOVQ g(CX), SI
MOVQ SP, DI
ADDQ AX, DI
MOVQ -8(DI), BX
MOVQ BX, (g_sched+gobuf_pc)(SI)
MOVQ 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.)
MOVQ g(CX), BX
MOVQ g_m(BX), BX
MOVQ m_g0(BX), SI
MOVQ SI, g(CX)
MOVQ (g_sched+gobuf_sp)(SI), SP
MOVQ 0(SP), AX
MOVQ 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.
CMPQ R8, $0
JNE 3(PC)
MOVQ $runtime·dropm(SB), AX
CALL AX
// Done!
RET
// void setg(G*); set g. for use by needm.
TEXT runtime·setg(SB), NOSPLIT, $0-8
MOVQ gg+0(FP), BX
#ifdef GOOS_windows
CMPQ BX, $0
JNE settls
MOVQ $0, 0x28(GS)
RET
settls:
MOVQ g_m(BX), AX
LEAQ m_tls(AX), AX
MOVQ AX, 0x28(GS)
#endif
get_tls(CX)
MOVQ BX, g(CX)
RET
// void setg_gcc(G*); set g called from gcc.
TEXT setg_gcc<>(SB),NOSPLIT,$0
get_tls(AX)
MOVQ DI, 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)
MOVQ g(CX), AX
CMPQ (g_stack+stack_hi)(AX), SP
JHI 2(PC)
INT $3
CMPQ SP, (g_stack+stack_lo)(AX)
JHI 2(PC)
INT $3
RET
TEXT runtime·getcallerpc(SB),NOSPLIT,$8-16
MOVQ argp+0(FP),AX // addr of first arg
MOVQ -8(AX),AX // get calling pc
CMPQ AX, runtime·stackBarrierPC(SB)
JNE nobar
// Get original return PC.
CALL runtime·nextBarrierPC(SB)
MOVQ 0(SP), AX
nobar:
MOVQ AX, ret+8(FP)
RET
TEXT runtime·setcallerpc(SB),NOSPLIT,$8-16
MOVQ argp+0(FP),AX // addr of first arg
MOVQ pc+8(FP), BX
MOVQ -8(AX), CX
CMPQ CX, runtime·stackBarrierPC(SB)
JEQ setbar
MOVQ BX, -8(AX) // set calling pc
RET
setbar:
// Set the stack barrier return PC.
MOVQ BX, 0(SP)
CALL runtime·setNextBarrierPC(SB)
RET
TEXT runtime·getcallersp(SB),NOSPLIT,$0-16
MOVQ argp+0(FP), AX
MOVQ AX, ret+8(FP)
RET
// func cputicks() int64
TEXT runtime·cputicks(SB),NOSPLIT,$0-0
CMPB runtime·lfenceBeforeRdtsc(SB), $1
JNE mfence
LFENCE
JMP done
mfence:
MFENCE
done:
RDTSC
SHLQ $32, DX
ADDQ DX, AX
MOVQ AX, ret+0(FP)
RET
// 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,$32-24
GO_ARGS
NO_LOCAL_POINTERS
MOVQ p+0(FP), AX
MOVQ h+8(FP), BX
MOVQ 8(DX), CX
MOVQ AX, 0(SP)
MOVQ BX, 8(SP)
MOVQ CX, 16(SP)
CALL runtime·memhash(SB)
MOVQ 24(SP), AX
MOVQ AX, ret+16(FP)
RET
// hash function using AES hardware instructions
TEXT runtime·aeshash(SB),NOSPLIT,$0-32
MOVQ p+0(FP), AX // ptr to data
MOVQ s+16(FP), CX // size
LEAQ ret+24(FP), DX
JMP runtime·aeshashbody(SB)
TEXT runtime·aeshashstr(SB),NOSPLIT,$0-24
MOVQ p+0(FP), AX // ptr to string struct
MOVQ 8(AX), CX // length of string
MOVQ (AX), AX // string data
LEAQ ret+16(FP), DX
JMP runtime·aeshashbody(SB)
// AX: data
// CX: length
// DX: address to put return value
TEXT runtime·aeshashbody(SB),NOSPLIT,$0-0
// Fill an SSE register with our seeds.
MOVQ h+8(FP), X0 // 64 bits of per-table hash seed
PINSRW $4, CX, X0 // 16 bits of length
PSHUFHW $0, X0, X0 // repeat length 4 times total
MOVO X0, X1 // save unscrambled seed
PXOR runtime·aeskeysched(SB), X0 // xor in per-process seed
AESENC X0, X0 // scramble seed
CMPQ CX, $16
JB aes0to15
JE aes16
CMPQ CX, $32
JBE aes17to32
CMPQ CX, $64
JBE aes33to64
CMPQ CX, $128
JBE aes65to128
JMP aes129plus
aes0to15:
TESTQ CX, CX
JE aes0
ADDQ $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), X1
ADDQ CX, CX
MOVQ $masks<>(SB), AX
PAND (AX)(CX*8), X1
final1:
AESENC X0, X1 // scramble input, xor in seed
AESENC X1, X1 // scramble combo 2 times
AESENC X1, X1
MOVQ X1, (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), X1
ADDQ CX, CX
MOVQ $shifts<>(SB), AX
PSHUFB (AX)(CX*8), X1
JMP final1
aes0:
// Return scrambled input seed
AESENC X0, X0
MOVQ X0, (DX)
RET
aes16:
MOVOU (AX), X1
JMP final1
aes17to32:
// make second starting seed
PXOR runtime·aeskeysched+16(SB), X1
AESENC X1, X1
// load data to be hashed
MOVOU (AX), X2
MOVOU -16(AX)(CX*1), X3
// scramble 3 times
AESENC X0, X2
AESENC X1, X3
AESENC X2, X2
AESENC X3, X3
AESENC X2, X2
AESENC X3, X3
// combine results
PXOR X3, X2
MOVQ X2, (DX)
RET
aes33to64:
// make 3 more starting seeds
MOVO X1, X2
MOVO X1, X3
PXOR runtime·aeskeysched+16(SB), X1
PXOR runtime·aeskeysched+32(SB), X2
PXOR runtime·aeskeysched+48(SB), X3
AESENC X1, X1
AESENC X2, X2
AESENC X3, X3
MOVOU (AX), X4
MOVOU 16(AX), X5
MOVOU -32(AX)(CX*1), X6
MOVOU -16(AX)(CX*1), X7
AESENC X0, X4
AESENC X1, X5
AESENC X2, X6
AESENC X3, X7
AESENC X4, X4
AESENC X5, X5
AESENC X6, X6
AESENC X7, X7
AESENC X4, X4
AESENC X5, X5
AESENC X6, X6
AESENC X7, X7
PXOR X6, X4
PXOR X7, X5
PXOR X5, X4
MOVQ X4, (DX)
RET
aes65to128:
// make 7 more starting seeds
MOVO X1, X2
MOVO X1, X3
MOVO X1, X4
MOVO X1, X5
MOVO X1, X6
MOVO X1, X7
PXOR runtime·aeskeysched+16(SB), X1
PXOR runtime·aeskeysched+32(SB), X2
PXOR runtime·aeskeysched+48(SB), X3