// Copyright 2018 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|NOFRAME|TOPFRAME, $0

// save m->g0 = g0

MOVD $runtime·g0(SB), runtime·m0+m_g0(SB)

// save m0 to g0->m

MOVD $runtime·m0(SB), runtime·g0+g_m(SB)

// set g to g0

MOVD $runtime·g0(SB), g

CALLNORESUME runtime·check(SB)

#ifdef GOOS_js

CALLNORESUME runtime·args(SB)

#endif

CALLNORESUME runtime·osinit(SB)

CALLNORESUME runtime·schedinit(SB)

MOVD $runtime·mainPC(SB), 0(SP)

CALLNORESUME runtime·newproc(SB)

CALL runtime·mstart(SB) // WebAssembly stack will unwind when switching to another goroutine

UNDEF

TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0

CALL runtime·mstart0(SB)

RET // not reached

DATA runtime·mainPC+0(SB)/8,$runtime·main(SB)

GLOBL runtime·mainPC(SB),RODATA,$8

// func checkASM() bool

TEXT ·checkASM(SB), NOSPLIT, $0-1

MOVB $1, ret+0(FP)

RET

TEXT runtime·gogo(SB), NOSPLIT, $0-8

MOVD buf+0(FP), R0

MOVD gobuf_g(R0), R1

MOVD 0(R1), R2 // make sure g != nil

MOVD R1, g

MOVD gobuf_sp(R0), SP

// Put target PC at -8(SP), wasm_pc_f_loop will pick it up

Get SP

I32Const $8

I32Sub

I64Load gobuf_pc(R0)

I64Store $0

MOVD gobuf_ctxt(R0), CTXT

// clear to help garbage collector

MOVD $0, gobuf_sp(R0)

MOVD $0, gobuf_ctxt(R0)

I32Const $1

Return

// 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

// CTXT = fn

MOVD fn+0(FP), CTXT

// R1 = g.m

MOVD g_m(g), R1

// R2 = g0

MOVD m_g0(R1), R2

// save state in g->sched

MOVD 0(SP), g_sched+gobuf_pc(g) // caller's PC

MOVD $fn+0(FP), g_sched+gobuf_sp(g) // caller's SP

// if g == g0 call badmcall

Get g

Get R2

I64Eq

If

JMP runtime·badmcall(SB)

End

// switch to g0's stack

I64Load (g_sched+gobuf_sp)(R2)

I64Const $8

I64Sub

I32WrapI64

Set SP

// set arg to current g

MOVD g, 0(SP)

// switch to g0

MOVD R2, g

// call fn

Get CTXT

I32WrapI64

I64Load $0

CALL

Get SP

I32Const $8

I32Add

Set SP

JMP runtime·badmcall2(SB)

// func systemstack(fn func())

TEXT runtime·systemstack(SB), NOSPLIT, $0-8

// R0 = fn

MOVD fn+0(FP), R0

// R1 = g.m

MOVD g_m(g), R1

// R2 = g0

MOVD m_g0(R1), R2

// if g == g0

Get g

Get R2

I64Eq

If

// no switch:

MOVD R0, CTXT

Get CTXT

I32WrapI64

I64Load $0

JMP

End

// if g != m.curg

Get g

I64Load m_curg(R1)

I64Ne

If

CALLNORESUME runtime·badsystemstack(SB)

CALLNORESUME runtime·abort(SB)

End

// switch:

// save state in g->sched. Pretend to

// be systemstack_switch if the G stack is scanned.

MOVD $runtime·systemstack_switch(SB), g_sched+gobuf_pc(g)

MOVD SP, g_sched+gobuf_sp(g)

// switch to g0

MOVD R2, g

// make it look like mstart called systemstack on g0, to stop traceback

I64Load (g_sched+gobuf_sp)(R2)

I64Const $8

I64Sub

Set R3

MOVD $runtime·mstart(SB), 0(R3)

MOVD R3, SP

// call fn

MOVD R0, CTXT

Get CTXT

I32WrapI64

I64Load $0

CALL

// switch back to g

MOVD g_m(g), R1

MOVD m_curg(R1), R2

MOVD R2, g

MOVD g_sched+gobuf_sp(R2), SP

MOVD $0, g_sched+gobuf_sp(R2)

RET

TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0

RET

TEXT runtime·abort(SB),NOSPLIT|NOFRAME,$0-0

UNDEF

// AES hashing not implemented for wasm

TEXT runtime·memhash(SB),NOSPLIT|NOFRAME,$0-32

JMP runtime·memhashFallback(SB)

TEXT runtime·strhash(SB),NOSPLIT|NOFRAME,$0-24

JMP runtime·strhashFallback(SB)

TEXT runtime·memhash32(SB),NOSPLIT|NOFRAME,$0-24

JMP runtime·memhash32Fallback(SB)

TEXT runtime·memhash64(SB),NOSPLIT|NOFRAME,$0-24

JMP runtime·memhash64Fallback(SB)

TEXT runtime·asminit(SB), NOSPLIT, $0-0

// No per-thread init.

RET

TEXT ·publicationBarrier(SB), NOSPLIT, $0-0

RET

TEXT runtime·procyield(SB), NOSPLIT, $0-0 // FIXME

RET

TEXT runtime·breakpoint(SB), NOSPLIT, $0-0

UNDEF

// func switchToCrashStack0(fn func())

TEXT runtime·switchToCrashStack0(SB), NOSPLIT, $0-8

MOVD fn+0(FP), CTXT // context register

MOVD g_m(g), R2 // curm

// set g to gcrash

MOVD $runtime·gcrash(SB), g // g = &gcrash

MOVD R2, g_m(g) // g.m = curm

MOVD g, m_g0(R2) // curm.g0 = g

// switch to crashstack

I64Load (g_stack+stack_hi)(g)

I64Const $(-4*8)

I64Add

I32WrapI64

Set SP

// call target function

Get CTXT

I32WrapI64

I64Load $0

CALL

// should never return

CALL runtime·abort(SB)

UNDEF

// 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

// R1 = g.m

MOVD g_m(g), R1

// R2 = g0

MOVD m_g0(R1), R2

// Set g->sched to context in f.

NOP SP // tell vet SP changed - stop checking offsets

MOVD 0(SP), g_sched+gobuf_pc(g)

MOVD $8(SP), g_sched+gobuf_sp(g) // f's SP

MOVD CTXT, g_sched+gobuf_ctxt(g)

// Cannot grow scheduler stack (m->g0).

Get g

Get R2

I64Eq

If

CALLNORESUME runtime·badmorestackg0(SB)

CALLNORESUME runtime·abort(SB)

End

// Cannot grow signal stack (m->gsignal).

Get g

I64Load m_gsignal(R1)

I64Eq

If

CALLNORESUME runtime·badmorestackgsignal(SB)

CALLNORESUME runtime·abort(SB)

End

// Called from f.

// Set m->morebuf to f's caller.

MOVD 8(SP), m_morebuf+gobuf_pc(R1)

MOVD $16(SP), m_morebuf+gobuf_sp(R1) // f's caller's SP

MOVD g, m_morebuf+gobuf_g(R1)

// Call newstack on m->g0's stack.

MOVD R2, g

MOVD g_sched+gobuf_sp(R2), SP

CALL runtime·newstack(SB)

UNDEF // crash if newstack returns

// morestack but not preserving ctxt.

TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0

MOVD $0, CTXT

JMP runtime·morestack(SB)

TEXT ·asmcgocall(SB), NOSPLIT, $0-0

UNDEF

#define DISPATCH(NAME, MAXSIZE) \

Get R0; \

I64Const $MAXSIZE; \

I64LeU; \

If; \

JMP NAME(SB); \

End

TEXT ·reflectcall(SB), NOSPLIT, $0-48

I64Load fn+8(FP)

I64Eqz

If

CALLNORESUME runtime·sigpanic<ABIInternal>(SB)

End

MOVW frameSize+32(FP), R0

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)

JMP runtime·badreflectcall(SB)

#define CALLFN(NAME, MAXSIZE) \

TEXT NAME(SB), WRAPPER, $MAXSIZE-48; \

NO_LOCAL_POINTERS; \

MOVW stackArgsSize+24(FP), R0; \

\

Get R0; \

I64Eqz; \

Not; \

If; \

Get SP; \

I64Load stackArgs+16(FP); \

I32WrapI64; \

I64Load stackArgsSize+24(FP); \

I32WrapI64; \

MemoryCopy; \

End; \

\

MOVD f+8(FP), CTXT; \

Get CTXT; \

I32WrapI64; \

I64Load $0; \

CALL; \

\

I64Load32U stackRetOffset+28(FP); \

Set R0; \

\

MOVD stackArgsType+0(FP), RET0; \

\

I64Load stackArgs+16(FP); \

Get R0; \

I64Add; \

Set RET1; \

\

Get SP; \

I64ExtendI32U; \

Get R0; \

I64Add; \

Set RET2; \

\

I64Load32U stackArgsSize+24(FP); \

Get R0; \

I64Sub; \

Set RET3; \

\

CALL callRet<>(SB); \

RET

// callRet copies return values back at the end of call*. This is a

// separate function so it can allocate stack space for the arguments

// to reflectcallmove. It does not follow the Go ABI; it expects its

// arguments in registers.

TEXT callRet<>(SB), NOSPLIT, $40-0

NO_LOCAL_POINTERS

MOVD RET0, 0(SP)

MOVD RET1, 8(SP)

MOVD RET2, 16(SP)

MOVD RET3, 24(SP)

MOVD $0, 32(SP)

CALL runtime·reflectcallmove(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)

TEXT runtime·goexit(SB), NOSPLIT|TOPFRAME, $0-0

NOP // first PC of goexit is skipped

CALL runtime·goexit1(SB) // does not return

UNDEF

TEXT runtime·cgocallback(SB), NOSPLIT, $0-24

UNDEF

// gcWriteBarrier informs the GC about heap pointer writes.

//

// gcWriteBarrier does NOT follow the Go ABI. It accepts the

// number of bytes of buffer needed as a wasm argument

// (put on the TOS by the caller, lives in local R0 in this body)

// and returns a pointer to the buffer space as a wasm result

// (left on the TOS in this body, appears on the wasm stack

// in the caller).

TEXT gcWriteBarrier<>(SB), NOSPLIT, $0

Loop

// R3 = g.m

MOVD g_m(g), R3

// R4 = p

MOVD m_p(R3), R4

// R5 = wbBuf.next

MOVD p_wbBuf+wbBuf_next(R4), R5

// Increment wbBuf.next

Get R5

Get R0

I64Add

Set R5

// Is the buffer full?

Get R5

I64Load (p_wbBuf+wbBuf_end)(R4)

I64LeU

If

// Commit to the larger buffer.

MOVD R5, p_wbBuf+wbBuf_next(R4)

// Make return value (the original next position)

Get R5

Get R0

I64Sub

Return

End

// Flush

CALLNORESUME runtime·wbBufFlush(SB)

// Retry

Br $0

End

TEXT runtime·gcWriteBarrier1<ABIInternal>(SB),NOSPLIT,$0

I64Const $8

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier2<ABIInternal>(SB),NOSPLIT,$0

I64Const $16

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier3<ABIInternal>(SB),NOSPLIT,$0

I64Const $24

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier4<ABIInternal>(SB),NOSPLIT,$0

I64Const $32

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier5<ABIInternal>(SB),NOSPLIT,$0

I64Const $40

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier6<ABIInternal>(SB),NOSPLIT,$0

I64Const $48

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier7<ABIInternal>(SB),NOSPLIT,$0

I64Const $56

Call gcWriteBarrier<>(SB)

Return

TEXT runtime·gcWriteBarrier8<ABIInternal>(SB),NOSPLIT,$0

I64Const $64

Call gcWriteBarrier<>(SB)

Return

TEXT wasm_pc_f_loop(SB),NOSPLIT,$0

// Call the function for the current PC_F. Repeat until PAUSE != 0 indicates pause or exit.

// The WebAssembly stack may unwind, e.g. when switching goroutines.

// The Go stack on the linear memory is then used to jump to the correct functions

// with this loop, without having to restore the full WebAssembly stack.

// It is expected to have a pending call before entering the loop, so check PAUSE first.

Get PAUSE

I32Eqz

If

loop:

Loop

// Get PC_B & PC_F from -8(SP)

Get SP

I32Const $8

I32Sub

I32Load16U $0 // PC_B

Get SP

I32Const $8

I32Sub

I32Load16U $2 // PC_F

CallIndirect $0

Drop

Get PAUSE

I32Eqz

BrIf loop

End

End

I32Const $0

Set PAUSE

Return

// wasm_pc_f_loop_export is like wasm_pc_f_loop, except that this takes an

// argument (on Wasm stack) that is a PC_F, and the loop stops when we get

// to that PC in a normal return (not unwinding).

// This is for handling an wasmexport function when it needs to switch the

// stack.

TEXT wasm_pc_f_loop_export(SB),NOSPLIT,$0

Get PAUSE

I32Eqz

outer:

If

// R1 is whether a function return normally (0) or unwinding (1).

// Start with unwinding.

I32Const $1

Set R1

loop:

Loop

// Get PC_F & PC_B from -8(SP)

Get SP

I32Const $8

I32Sub

I32Load16U $2 // PC_F

Tee R2

Get R0

I32Eq

If // PC_F == R0, we're at the stop PC

Get R1

I32Eqz

// Break if it is a normal return

BrIf outer // actually jump to after the corresponding End

End

Get SP

I32Const $8

I32Sub

I32Load16U $0 // PC_B

Get R2 // PC_F

CallIndirect $0

Set R1 // save return/unwinding state for next iteration

Get PAUSE

I32Eqz

BrIf loop

End

End

I32Const $0

Set PAUSE

Return

TEXT wasm_export_lib(SB),NOSPLIT,$0

UNDEF

TEXT runtime·pause(SB), NOSPLIT, $0-8

MOVD newsp+0(FP), SP

I32Const $1

Set PAUSE

RETUNWIND

// Called if a wasmexport function is called before runtime initialization

TEXT runtime·notInitialized(SB), NOSPLIT, $0

MOVD $runtime·wasmStack+(m0Stack__size-16-8)(SB), SP

I32Const $0 // entry PC_B

Call runtime·notInitialized1(SB)

Drop

I32Const $0 // entry PC_B

Call runtime·abort(SB)

UNDEF