// Copyright 2011 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 "zasm_GOOS_GOARCH.h"
#include "../../cmd/ld/textflag.h"
// maxargs should be divisible by 2, as Windows stack
// must be kept 16-byte aligned on syscall entry.
#define maxargs 16
// void runtime·asmstdcall(void *c);
TEXT runtime·asmstdcall(SB),NOSPLIT,$0
// asmcgocall will put first argument into CX.
PUSHQ CX // save for later
MOVQ libcall_fn(CX), AX
MOVQ libcall_args(CX), SI
MOVQ libcall_n(CX), CX
// SetLastError(0).
MOVQ 0x30(GS), DI
MOVL $0, 0x68(DI)
SUBQ $(maxargs*8), SP // room for args
// Fast version, do not store args on the stack.
CMPL CX, $4
JLE loadregs
// Check we have enough room for args.
CMPL CX, $maxargs
JLE 2(PC)
INT $3 // not enough room -> crash
// Copy args to the stack.
MOVQ SP, DI
CLD
REP; MOVSQ
MOVQ SP, SI
loadregs:
// Load first 4 args into correspondent registers.
MOVQ 0(SI), CX
MOVQ 8(SI), DX
MOVQ 16(SI), R8
MOVQ 24(SI), R9
// Call stdcall function.
CALL AX
ADDQ $(maxargs*8), SP
// Return result.
POPQ CX
MOVQ AX, libcall_r1(CX)
// GetLastError().
MOVQ 0x30(GS), DI
MOVL 0x68(DI), AX
MOVQ AX, libcall_err(CX)
RET
TEXT runtime·badsignal2(SB),NOSPLIT,$48
// stderr
MOVQ $-12, CX // stderr
MOVQ CX, 0(SP)
MOVQ runtime·GetStdHandle(SB), AX
CALL AX
MOVQ AX, CX // handle
MOVQ CX, 0(SP)
MOVQ $runtime·badsignalmsg(SB), DX // pointer
MOVQ DX, 8(SP)
MOVL $runtime·badsignallen(SB), R8 // count
MOVQ R8, 16(SP)
LEAQ 40(SP), R9 // written count
MOVQ $0, 0(R9)
MOVQ R9, 24(SP)
MOVQ $0, 32(SP) // overlapped
MOVQ runtime·WriteFile(SB), AX
CALL AX
RET
// faster get/set last error
TEXT runtime·getlasterror(SB),NOSPLIT,$0
MOVQ 0x30(GS), AX
MOVL 0x68(AX), AX
RET
TEXT runtime·setlasterror(SB),NOSPLIT,$0
MOVL err+0(FP), AX
MOVQ 0x30(GS), CX
MOVL AX, 0x68(CX)
RET
// Called by Windows as a Vectored Exception Handler (VEH).
// First argument is pointer to struct containing
// exception record and context pointers.
// Return 0 for 'not handled', -1 for handled.
TEXT runtime·sigtramp(SB),NOSPLIT,$0-0
// CX: PEXCEPTION_POINTERS ExceptionInfo
// DI SI BP BX R12 R13 R14 R15 registers and DF flag are preserved
// as required by windows callback convention.
PUSHFQ
SUBQ $88, SP
MOVQ DI, 80(SP)
MOVQ SI, 72(SP)
MOVQ BP, 64(SP)
MOVQ BX, 56(SP)
MOVQ R12, 48(SP)
MOVQ R13, 40(SP)
MOVQ R14, 32(SP)
MOVQ R15, 24(SP)
MOVQ 0(CX), BX // ExceptionRecord*
MOVQ 8(CX), CX // Context*
// fetch g
get_tls(DX)
MOVQ m(DX), AX
CMPQ AX, $0
JNE 2(PC)
CALL runtime·badsignal2(SB)
MOVQ g(DX), DX
// call sighandler(ExceptionRecord*, Context*, G*)
MOVQ BX, 0(SP)
MOVQ CX, 8(SP)
MOVQ DX, 16(SP)
CALL runtime·sighandler(SB)
// AX is set to report result back to Windows
// restore registers as required for windows callback
MOVQ 24(SP), R15
MOVQ 32(SP), R14
MOVQ 40(SP), R13
MOVQ 48(SP), R12
MOVQ 56(SP), BX
MOVQ 64(SP), BP
MOVQ 72(SP), SI
MOVQ 80(SP), DI
ADDQ $88, SP
POPFQ
RET
TEXT runtime·ctrlhandler(SB),NOSPLIT,$8
MOVQ CX, 16(SP) // spill
MOVQ $runtime·ctrlhandler1(SB), CX
MOVQ CX, 0(SP)
CALL runtime·externalthreadhandler(SB)
RET
TEXT runtime·profileloop(SB),NOSPLIT,$8
MOVQ $runtime·profileloop1(SB), CX
MOVQ CX, 0(SP)
CALL runtime·externalthreadhandler(SB)
RET
TEXT runtime·externalthreadhandler(SB),NOSPLIT,$0
PUSHQ BP
MOVQ SP, BP
PUSHQ BX
PUSHQ SI
PUSHQ DI
PUSHQ 0x28(GS)
MOVQ SP, DX
// setup dummy m, g
SUBQ $m_end, SP // space for M
MOVQ SP, 0(SP)
MOVQ $m_end, 8(SP)
CALL runtime·memclr(SB) // smashes AX,BX,CX
LEAQ m_tls(SP), CX
MOVQ CX, 0x28(GS)
MOVQ SP, m(CX)
MOVQ SP, BX
SUBQ $g_end, SP // space for G
MOVQ SP, g(CX)
MOVQ SP, m_g0(BX)
MOVQ SP, 0(SP)
MOVQ $g_end, 8(SP)
CALL runtime·memclr(SB) // smashes AX,BX,CX
LEAQ -8192(SP), CX
MOVQ CX, g_stackguard(SP)
MOVQ DX, g_stackbase(SP)
PUSHQ 32(BP) // arg for handler
CALL 16(BP)
POPQ CX
get_tls(CX)
MOVQ g(CX), CX
MOVQ g_stackbase(CX), SP
POPQ 0x28(GS)
POPQ DI
POPQ SI
POPQ BX
POPQ BP
RET
GLOBL runtime·cbctxts(SB), $8
TEXT runtime·callbackasm1(SB),NOSPLIT,$0
// Construct args vector for cgocallback().
// By windows/amd64 calling convention first 4 args are in CX, DX, R8, R9
// args from the 5th on are on the stack.
// In any case, even if function has 0,1,2,3,4 args, there is reserved
// but uninitialized "shadow space" for the first 4 args.
// The values are in registers.
MOVQ CX, (16+0)(SP)
MOVQ DX, (16+8)(SP)
MOVQ R8, (16+16)(SP)
MOVQ R9, (16+24)(SP)
// remove return address from stack, we are not returning there
MOVQ 0(SP), AX
ADDQ $8, SP
// determine index into runtime·cbctxts table
SUBQ $runtime·callbackasm(SB), AX
MOVQ $0, DX
MOVQ $5, CX // divide by 5 because each call instruction in runtime·callbacks is 5 bytes long
DIVL CX,
// find correspondent runtime·cbctxts table entry
MOVQ runtime·cbctxts(SB), CX
MOVQ -8(CX)(AX*8), AX
// extract callback context
MOVQ cbctxt_argsize(AX), DX
MOVQ cbctxt_gobody(AX), AX
// preserve whatever's at the memory location that
// the callback will use to store the return value
LEAQ 8(SP), CX // args vector, skip return address
PUSHQ 0(CX)(DX*1) // store 8 bytes from just after the args array
ADDQ $8, DX // extend argsize by size of return value
// DI SI BP BX R12 R13 R14 R15 registers and DF flag are preserved
// as required by windows callback convention.
PUSHFQ
SUBQ $64, SP
MOVQ DI, 56(SP)
MOVQ SI, 48(SP)
MOVQ BP, 40(SP)
MOVQ BX, 32(SP)
MOVQ R12, 24(SP)
MOVQ R13, 16(SP)
MOVQ R14, 8(SP)
MOVQ R15, 0(SP)
// prepare call stack. use SUBQ to hide from stack frame checks
// cgocallback(Go func, void *frame, uintptr framesize)
SUBQ $24, SP
MOVQ DX, 16(SP) // argsize (including return value)
MOVQ CX, 8(SP) // callback parameters
MOVQ AX, 0(SP) // address of target Go function
CLD
CALL runtime·cgocallback_gofunc(SB)
MOVQ 0(SP), AX
MOVQ 8(SP), CX
MOVQ 16(SP), DX
ADDQ $24, SP
// restore registers as required for windows callback
MOVQ 0(SP), R15
MOVQ 8(SP), R14
MOVQ 16(SP), R13
MOVQ 24(SP), R12
MOVQ 32(SP), BX
MOVQ 40(SP), BP
MOVQ 48(SP), SI
MOVQ 56(SP), DI
ADDQ $64, SP
POPFQ
MOVL -8(CX)(DX*1), AX // return value
POPQ -8(CX)(DX*1) // restore bytes just after the args
RET
// uint32 tstart_stdcall(M *newm);
TEXT runtime·tstart_stdcall(SB),NOSPLIT,$0
// CX contains first arg newm
MOVQ m_g0(CX), DX // g
// Layout new m scheduler stack on os stack.
MOVQ SP, AX
MOVQ AX, g_stackbase(DX)
SUBQ $(64*1024), AX // stack size
MOVQ AX, g_stackguard(DX)
// Set up tls.
LEAQ m_tls(CX), SI
MOVQ SI, 0x28(GS)
MOVQ CX, m(SI)
MOVQ DX, g(SI)
// Someday the convention will be D is always cleared.
CLD
CALL runtime·stackcheck(SB) // clobbers AX,CX
CALL runtime·mstart(SB)
XORL AX, AX // return 0 == success
RET
// set tls base to DI
TEXT runtime·settls(SB),NOSPLIT,$0
MOVQ DI, 0x28(GS)
RET
// Sleep duration is in 100ns units.
TEXT runtime·usleep1(SB),NOSPLIT,$0
MOVL duration+0(FP), BX
MOVQ $runtime·usleep2(SB), AX // to hide from 6l
// Execute call on m->g0 stack, in case we are not actually
// calling a system call wrapper, like when running under WINE.
get_tls(R15)
CMPQ R15, $0
JNE 3(PC)
// Not a Go-managed thread. Do not switch stack.
CALL AX
RET
MOVQ m(R15), R13
// leave pc/sp for cpu profiler
MOVQ (SP), R12
MOVQ R12, m_libcallpc(R13)
MOVQ g(R15), R12
MOVQ R12, m_libcallg(R13)
// sp must be the last, because once async cpu profiler finds
// all three values to be non-zero, it will use them
LEAQ 8(SP), R12
MOVQ R12, m_libcallsp(R13)
MOVQ m_g0(R13), R14
CMPQ g(R15), R14
JNE usleep1_switch
// executing on m->g0 already
CALL AX
JMP usleep1_ret
usleep1_switch:
// Switch to m->g0 stack and back.
MOVQ (g_sched+gobuf_sp)(R14), R14
MOVQ SP, -8(R14)
LEAQ -8(R14), SP
CALL AX
MOVQ 0(SP), SP
usleep1_ret:
MOVQ $0, m_libcallsp(R13)
RET
// Runs on OS stack. duration (in 100ns units) is in BX.
TEXT runtime·usleep2(SB),NOSPLIT,$8
// Want negative 100ns units.
NEGQ BX
MOVQ SP, R8 // ptime
MOVQ BX, (R8)
MOVQ $-1, CX // handle
MOVQ $0, DX // alertable
MOVQ runtime·NtWaitForSingleObject(SB), AX
CALL AX
RET