--- /dev/null
+// Copyright 2022 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"
+
+#define REGCTXT R29
+
+TEXT runtime·rt0_go(SB),NOSPLIT,$0
+ // R3 = stack; R4 = argc; R5 = argv
+
+ ADDV $-24, R3
+ MOVW R4, 8(R3) // argc
+ MOVV R5, 16(R3) // argv
+
+ // create istack out of the given (operating system) stack.
+ // _cgo_init may update stackguard.
+ MOVV $runtime·g0(SB), g
+ MOVV $(-64*1024), R30
+ ADDV R30, R3, R19
+ MOVV R19, g_stackguard0(g)
+ MOVV R19, g_stackguard1(g)
+ MOVV R19, (g_stack+stack_lo)(g)
+ MOVV R3, (g_stack+stack_hi)(g)
+
+ // if there is a _cgo_init, call it using the gcc ABI.
+ MOVV _cgo_init(SB), R25
+ BEQ R25, nocgo
+
+ MOVV R0, R7 // arg 3: not used
+ MOVV R0, R6 // arg 2: not used
+ MOVV $setg_gcc<>(SB), R5 // arg 1: setg
+ MOVV g, R4 // arg 0: G
+ JAL (R25)
+
+nocgo:
+ // update stackguard after _cgo_init
+ MOVV (g_stack+stack_lo)(g), R19
+ ADDV $const__StackGuard, R19
+ MOVV R19, g_stackguard0(g)
+ MOVV R19, g_stackguard1(g)
+
+ // set the per-goroutine and per-mach "registers"
+ MOVV $runtime·m0(SB), R19
+
+ // save m->g0 = g0
+ MOVV g, m_g0(R19)
+ // save m0 to g0->m
+ MOVV R19, g_m(g)
+
+ JAL runtime·check(SB)
+
+ // args are already prepared
+ JAL runtime·args(SB)
+ JAL runtime·osinit(SB)
+ JAL runtime·schedinit(SB)
+
+ // create a new goroutine to start program
+ MOVV $runtime·mainPC(SB), R19 // entry
+ ADDV $-16, R3
+ MOVV R19, 8(R3)
+ MOVV R0, 0(R3)
+ JAL runtime·newproc(SB)
+ ADDV $16, R3
+
+ // start this M
+ JAL runtime·mstart(SB)
+
+ MOVV R0, 1(R0)
+ RET
+
+DATA runtime·mainPC+0(SB)/8,$runtime·main(SB)
+GLOBL runtime·mainPC(SB),RODATA,$8
+
+TEXT runtime·breakpoint(SB),NOSPLIT|NOFRAME,$0-0
+ BREAK
+ RET
+
+TEXT runtime·asminit(SB),NOSPLIT|NOFRAME,$0-0
+ RET
+
+TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
+ JAL runtime·mstart0(SB)
+ RET // not reached
+
+/*
+ * go-routine
+ */
+
+// void gosave(Gobuf*)
+// save state in Gobuf; setjmp
+TEXT runtime·gosave(SB), NOSPLIT|NOFRAME, $0-8
+ MOVV buf+0(FP), R19
+ MOVV R3, gobuf_sp(R19)
+ MOVV R1, gobuf_pc(R19)
+ MOVV g, gobuf_g(R19)
+ MOVV R0, gobuf_lr(R19)
+ MOVV R0, gobuf_ret(R19)
+ // Assert ctxt is zero. See func save.
+ MOVV gobuf_ctxt(R19), R19
+ BEQ R19, 2(PC)
+ JAL runtime·badctxt(SB)
+ RET
+
+// void gogo(Gobuf*)
+// restore state from Gobuf; longjmp
+TEXT runtime·gogo(SB), NOSPLIT, $16-8
+ MOVV buf+0(FP), R4
+ MOVV gobuf_g(R4), g // make sure g is not nil
+ JAL runtime·save_g(SB)
+
+ MOVV 0(g), R5
+ MOVV gobuf_sp(R4), R3
+ MOVV gobuf_lr(R4), R1
+ MOVV gobuf_ret(R4), R19
+ MOVV gobuf_ctxt(R4), REGCTXT
+ MOVV R0, gobuf_sp(R4)
+ MOVV R0, gobuf_ret(R4)
+ MOVV R0, gobuf_lr(R4)
+ MOVV R0, gobuf_ctxt(R4)
+ MOVV gobuf_pc(R4), R6
+ JMP (R6)
+
+// void 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|NOFRAME, $0-8
+ // Save caller state in g->sched
+ MOVV R3, (g_sched+gobuf_sp)(g)
+ MOVV R1, (g_sched+gobuf_pc)(g)
+ MOVV R0, (g_sched+gobuf_lr)(g)
+ MOVV g, (g_sched+gobuf_g)(g)
+
+ // Switch to m->g0 & its stack, call fn.
+ MOVV g, R19
+ MOVV g_m(g), R4
+ MOVV m_g0(R4), g
+ JAL runtime·save_g(SB)
+ BNE g, R19, 2(PC)
+ JMP runtime·badmcall(SB)
+ MOVV fn+0(FP), REGCTXT // context
+ MOVV 0(REGCTXT), R5 // code pointer
+ MOVV (g_sched+gobuf_sp)(g), R3 // sp = m->g0->sched.sp
+ ADDV $-16, R3
+ MOVV R19, 8(R3)
+ MOVV R0, 0(R3)
+ JAL (R5)
+ JMP runtime·badmcall2(SB)
+
+// 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
+ UNDEF
+ JAL (R1) // make sure this function is not leaf
+ RET
+
+// func systemstack(fn func())
+TEXT runtime·systemstack(SB), NOSPLIT, $0-8
+ MOVV fn+0(FP), R19 // R19 = fn
+ MOVV R19, REGCTXT // context
+ MOVV g_m(g), R4 // R4 = m
+
+ MOVV m_gsignal(R4), R5 // R5 = gsignal
+ BEQ g, R5, noswitch
+
+ MOVV m_g0(R4), R5 // R5 = g0
+ BEQ g, R5, noswitch
+
+ MOVV m_curg(R4), R6
+ BEQ g, R6, switch
+
+ // Bad: g is not gsignal, not g0, not curg. What is it?
+ // Hide call from linker nosplit analysis.
+ MOVV $runtime·badsystemstack(SB), R7
+ JAL (R7)
+ JAL runtime·abort(SB)
+
+switch:
+ // save our state in g->sched. Pretend to
+ // be systemstack_switch if the G stack is scanned.
+ JAL gosave_systemstack_switch<>(SB)
+
+ // switch to g0
+ MOVV R5, g
+ JAL runtime·save_g(SB)
+ MOVV (g_sched+gobuf_sp)(g), R19
+ // make it look like mstart called systemstack on g0, to stop traceback
+ ADDV $-8, R19
+ MOVV $runtime·mstart(SB), R6
+ MOVV R6, 0(R19)
+ MOVV R19, R3
+
+ // call target function
+ MOVV 0(REGCTXT), R6 // code pointer
+ JAL (R6)
+
+ // switch back to g
+ MOVV g_m(g), R4
+ MOVV m_curg(R4), g
+ JAL runtime·save_g(SB)
+ MOVV (g_sched+gobuf_sp)(g), R3
+ MOVV R0, (g_sched+gobuf_sp)(g)
+ RET
+
+noswitch:
+ // already on m stack, just call directly
+ // Using a tail call here cleans up tracebacks since we won't stop
+ // at an intermediate systemstack.
+ MOVV 0(REGCTXT), R4 // code pointer
+ MOVV 0(R3), R1 // restore LR
+ ADDV $8, R3
+ JMP (R4)
+
+/*
+ * support for morestack
+ */
+
+// Called during function prolog when more stack is needed.
+// Caller has already loaded:
+// loong64: R5: LR
+//
+// 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|NOFRAME,$0-0
+ // Cannot grow scheduler stack (m->g0).
+ MOVV g_m(g), R7
+ MOVV m_g0(R7), R8
+ BNE g, R8, 3(PC)
+ JAL runtime·badmorestackg0(SB)
+ JAL runtime·abort(SB)
+
+ // Cannot grow signal stack (m->gsignal).
+ MOVV m_gsignal(R7), R8
+ BNE g, R8, 3(PC)
+ JAL runtime·badmorestackgsignal(SB)
+ JAL runtime·abort(SB)
+
+ // Called from f.
+ // Set g->sched to context in f.
+ MOVV R3, (g_sched+gobuf_sp)(g)
+ MOVV R1, (g_sched+gobuf_pc)(g)
+ MOVV R5, (g_sched+gobuf_lr)(g)
+ MOVV REGCTXT, (g_sched+gobuf_ctxt)(g)
+
+ // Called from f.
+ // Set m->morebuf to f's caller.
+ MOVV R5, (m_morebuf+gobuf_pc)(R7) // f's caller's PC
+ MOVV R3, (m_morebuf+gobuf_sp)(R7) // f's caller's SP
+ MOVV g, (m_morebuf+gobuf_g)(R7)
+
+ // Call newstack on m->g0's stack.
+ MOVV m_g0(R7), g
+ JAL runtime·save_g(SB)
+ MOVV (g_sched+gobuf_sp)(g), R3
+ // Create a stack frame on g0 to call newstack.
+ MOVV R0, -8(R3) // Zero saved LR in frame
+ ADDV $-8, R3
+ JAL runtime·newstack(SB)
+
+ // Not reached, but make sure the return PC from the call to newstack
+ // is still in this function, and not the beginning of the next.
+ UNDEF
+
+TEXT runtime·morestack_noctxt(SB),NOSPLIT|NOFRAME,$0-0
+ MOVV R0, REGCTXT
+ 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) \
+ MOVV $MAXSIZE, R30; \
+ SGTU R19, R30, R30; \
+ BNE R30, 3(PC); \
+ MOVV $NAME(SB), R4; \
+ JMP (R4)
+// Note: can't just "BR NAME(SB)" - bad inlining results.
+
+TEXT ·reflectcall(SB), NOSPLIT|NOFRAME, $0-48
+ MOVWU stackArgsSize+24(FP), R19
+ 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)
+ MOVV $runtime·badreflectcall(SB), R4
+ JMP (R4)
+
+#define CALLFN(NAME,MAXSIZE) \
+TEXT NAME(SB), WRAPPER, $MAXSIZE-24; \
+ NO_LOCAL_POINTERS; \
+ /* copy arguments to stack */ \
+ MOVV arg+16(FP), R4; \
+ MOVWU argsize+24(FP), R5; \
+ MOVV R3, R12; \
+ ADDV $8, R12; \
+ ADDV R12, R5; \
+ BEQ R12, R5, 6(PC); \
+ MOVBU (R4), R6; \
+ ADDV $1, R4; \
+ MOVBU R6, (R12); \
+ ADDV $1, R12; \
+ JMP -5(PC); \
+ /* call function */ \
+ MOVV f+8(FP), REGCTXT; \
+ MOVV (REGCTXT), R6; \
+ PCDATA $PCDATA_StackMapIndex, $0; \
+ JAL (R6); \
+ /* copy return values back */ \
+ MOVV argtype+0(FP), R7; \
+ MOVV arg+16(FP), R4; \
+ MOVWU n+24(FP), R5; \
+ MOVWU retoffset+28(FP), R6; \
+ ADDV $8, R3, R12; \
+ ADDV R6, R12; \
+ ADDV R6, R4; \
+ SUBVU R6, R5; \
+ JAL 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, $32-0
+ MOVV R7, 8(R3)
+ MOVV R4, 16(R3)
+ MOVV R12, 24(R3)
+ MOVV R5, 32(R3)
+ JAL 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·procyield(SB),NOSPLIT,$0-0
+ RET
+
+// Save state of caller into g->sched.
+// but using fake PC from systemstack_switch.
+// Must only be called from functions with no locals ($0)
+// or else unwinding from systemstack_switch is incorrect.
+// Smashes R19.
+TEXT gosave_systemstack_switch<>(SB),NOSPLIT|NOFRAME,$0
+ MOVV $runtime·systemstack_switch(SB), R19
+ ADDV $8, R19
+ MOVV R19, (g_sched+gobuf_pc)(g)
+ MOVV R3, (g_sched+gobuf_sp)(g)
+ MOVV R0, (g_sched+gobuf_lr)(g)
+ MOVV R0, (g_sched+gobuf_ret)(g)
+ // Assert ctxt is zero. See func save.
+ MOVV (g_sched+gobuf_ctxt)(g), R19
+ BEQ R19, 2(PC)
+ JAL runtime·abort(SB)
+ 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
+ MOVV fn+0(FP), R25
+ MOVV arg+8(FP), R4
+
+ MOVV R3, R12 // save original stack pointer
+ MOVV g, R13
+
+ // 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.
+ MOVV g_m(g), R5
+ MOVV m_gsignal(R5), R6
+ BEQ R6, g, g0
+ MOVV m_g0(R5), R6
+ BEQ R6, g, g0
+
+ JAL gosave_systemstack_switch<>(SB)
+ MOVV R6, g
+ JAL runtime·save_g(SB)
+ MOVV (g_sched+gobuf_sp)(g), R3
+
+ // Now on a scheduling stack (a pthread-created stack).
+g0:
+ // Save room for two of our pointers.
+ ADDV $-16, R3
+ MOVV R13, 0(R3) // save old g on stack
+ MOVV (g_stack+stack_hi)(R13), R13
+ SUBVU R12, R13
+ MOVV R13, 8(R3) // save depth in old g stack (can't just save SP, as stack might be copied during a callback)
+ JAL (R25)
+
+ // Restore g, stack pointer. R4 is return value.
+ MOVV 0(R3), g
+ JAL runtime·save_g(SB)
+ MOVV (g_stack+stack_hi)(g), R5
+ MOVV 8(R3), R6
+ SUBVU R6, R5
+ MOVV R5, R3
+
+ MOVW R4, ret+16(FP)
+ RET
+
+// func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
+// See cgocall.go for more details.
+TEXT ·cgocallback(SB),NOSPLIT,$24-24
+ NO_LOCAL_POINTERS
+
+ // Load m and g from thread-local storage.
+ MOVB runtime·iscgo(SB), R19
+ BEQ R19, nocgo
+ JAL runtime·load_g(SB)
+nocgo:
+
+ // 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.
+ BEQ g, needm
+
+ MOVV g_m(g), R12
+ MOVV R12, savedm-8(SP)
+ JMP havem
+
+needm:
+ MOVV g, savedm-8(SP) // g is zero, so is m.
+ MOVV $runtime·needm(SB), R4
+ JAL (R4)
+
+ // 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.
+ MOVV g_m(g), R12
+ MOVV m_g0(R12), R19
+ MOVV R3, (g_sched+gobuf_sp)(R19)
+
+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 8(R29) aka savedsp-16(SP).
+ MOVV m_g0(R12), R19
+ MOVV (g_sched+gobuf_sp)(R19), R13
+ MOVV R13, savedsp-24(SP) // must match frame size
+ MOVV R3, (g_sched+gobuf_sp)(R19)
+
+ // 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.
+ MOVV m_curg(R12), g
+ JAL runtime·save_g(SB)
+ MOVV (g_sched+gobuf_sp)(g), R13 // prepare stack as R13
+ MOVV (g_sched+gobuf_pc)(g), R4
+ MOVV R4, -(24+8)(R13) // "saved LR"; must match frame size
+ MOVV fn+0(FP), R5
+ MOVV frame+8(FP), R6
+ MOVV ctxt+16(FP), R7
+ MOVV $-(24+8)(R13), R3
+ MOVV R5, 8(R3)
+ MOVV R6, 16(R3)
+ MOVV R7, 24(R3)
+ JAL runtime·cgocallbackg(SB)
+
+ // Restore g->sched (== m->curg->sched) from saved values.
+ MOVV 0(R3), R4
+ MOVV R4, (g_sched+gobuf_pc)(g)
+ MOVV $(24+8)(R3), R13 // must match frame size
+ MOVV R13, (g_sched+gobuf_sp)(g)
+
+ // 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.)
+ MOVV g_m(g), R12
+ MOVV m_g0(R12), g
+ JAL runtime·save_g(SB)
+ MOVV (g_sched+gobuf_sp)(g), R3
+ MOVV savedsp-24(SP), R13 // must match frame size
+ MOVV R13, (g_sched+gobuf_sp)(g)
+
+ // 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.
+ MOVV savedm-8(SP), R12
+ BNE R12, droppedm
+ MOVV $runtime·dropm(SB), R4
+ JAL (R4)
+droppedm:
+
+ // Done!
+ RET
+
+// void setg(G*); set g. for use by needm.
+TEXT runtime·setg(SB), NOSPLIT, $0-8
+ MOVV gg+0(FP), g
+ // This only happens if iscgo, so jump straight to save_g
+ JAL runtime·save_g(SB)
+ RET
+
+// void setg_gcc(G*); set g called from gcc with g in R19
+TEXT setg_gcc<>(SB),NOSPLIT,$0-0
+ MOVV R19, g
+ JAL runtime·save_g(SB)
+ RET
+
+TEXT runtime·abort(SB),NOSPLIT|NOFRAME,$0-0
+ MOVW (R0), R0
+ UNDEF
+
+// AES hashing not implemented for loong64
+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·return0(SB), NOSPLIT, $0
+ MOVW $0, R19
+ RET
+
+// Called from cgo wrappers, this function returns g->m->curg.stack.hi.
+// Must obey the gcc calling convention.
+TEXT _cgo_topofstack(SB),NOSPLIT,$16
+ // g (R22) and REGTMP (R30) might be clobbered by load_g. They
+ // are callee-save in the gcc calling convention, so save them.
+ MOVV R30, savedREGTMP-16(SP)
+ MOVV g, savedG-8(SP)
+
+ JAL runtime·load_g(SB)
+ MOVV g_m(g), R19
+ MOVV m_curg(R19), R19
+ MOVV (g_stack+stack_hi)(R19), R4 // return value in R4
+
+ MOVV savedG-8(SP), g
+ MOVV savedREGTMP-16(SP), R30
+ RET
+
+// The top-most function running on a goroutine
+// returns to goexit+PCQuantum.
+TEXT runtime·goexit(SB),NOSPLIT|NOFRAME|TOPFRAME,$0-0
+ NOR R0, R0 // NOP
+ JAL runtime·goexit1(SB) // does not return
+ // traceback from goexit1 must hit code range of goexit
+ NOR R0, R0 // NOP
+
+TEXT ·checkASM(SB),NOSPLIT,$0-1
+ MOVW $1, R19
+ MOVB R19, ret+0(FP)
+ RET
+
+// gcWriteBarrier performs a heap pointer write and informs the GC.
+//
+// gcWriteBarrier does NOT follow the Go ABI. It takes two arguments:
+// - R27 is the destination of the write
+// - R28 is the value being written at R27.
+// It clobbers R30 (the linker temp register).
+// The act of CALLing gcWriteBarrier will clobber R1 (LR).
+// It does not clobber any other general-purpose registers,
+// but may clobber others (e.g., floating point registers).
+TEXT runtime·gcWriteBarrier(SB),NOSPLIT,$216
+ // Save the registers clobbered by the fast path.
+ MOVV R19, 208(R3)
+ MOVV R13, 216(R3)
+ MOVV g_m(g), R19
+ MOVV m_p(R19), R19
+ MOVV (p_wbBuf+wbBuf_next)(R19), R13
+ // Increment wbBuf.next position.
+ ADDV $16, R13
+ MOVV R13, (p_wbBuf+wbBuf_next)(R19)
+ MOVV (p_wbBuf+wbBuf_end)(R19), R19
+ MOVV R19, R30 // R30 is linker temp register
+ // Record the write.
+ MOVV R28, -16(R13) // Record value
+ MOVV (R27), R19 // TODO: This turns bad writes into bad reads.
+ MOVV R19, -8(R13) // Record *slot
+ // Is the buffer full?
+ BEQ R13, R30, flush
+ret:
+ MOVV 208(R3), R19
+ MOVV 216(R3), R13
+ // Do the write.
+ MOVV R28, (R27)
+ RET
+
+flush:
+ // Save all general purpose registers since these could be
+ // clobbered by wbBufFlush and were not saved by the caller.
+ MOVV R27, 8(R3) // Also first argument to wbBufFlush
+ MOVV R28, 16(R3) // Also second argument to wbBufFlush
+ // R1 is LR, which was saved by the prologue.
+ MOVV R2, 24(R3)
+ // R3 is SP.
+ MOVV R4, 32(R3)
+ MOVV R5, 40(R3)
+ MOVV R6, 48(R3)
+ MOVV R7, 56(R3)
+ MOVV R8, 64(R3)
+ MOVV R9, 72(R3)
+ MOVV R10, 80(R3)
+ MOVV R11, 88(R3)
+ MOVV R12, 96(R3)
+ // R13 already saved
+ MOVV R14, 104(R3)
+ MOVV R15, 112(R3)
+ MOVV R16, 120(R3)
+ MOVV R17, 128(R3)
+ MOVV R18, 136(R3)
+ // R19 already saved
+ MOVV R20, 144(R3)
+ MOVV R21, 152(R3)
+ // R22 is g.
+ MOVV R23, 160(R3)
+ MOVV R24, 168(R3)
+ MOVV R25, 176(R3)
+ MOVV R26, 184(R3)
+ // R27 already saved
+ // R28 already saved.
+ MOVV R29, 192(R3)
+ // R30 is tmp register.
+ MOVV R31, 200(R3)
+
+
+ // This takes arguments R27 and R28.
+ CALL runtime·wbBufFlush(SB)
+
+ MOVV 8(R3), R27
+ MOVV 16(R3), R28
+ MOVV 24(R3), R2
+ MOVV 32(R3), R4
+ MOVV 40(R3), R5
+ MOVV 48(R3), R6
+ MOVV 56(R3), R7
+ MOVV 64(R3), R8
+ MOVV 72(R3), R9
+ MOVV 80(R3), R10
+ MOVV 88(R3), R11
+ MOVV 96(R3), R12
+ MOVV 104(R3), R14
+ MOVV 112(R3), R15
+ MOVV 120(R3), R16
+ MOVV 128(R3), R17
+ MOVV 136(R3), R18
+ MOVV 144(R3), R20
+ MOVV 152(R3), R21
+ MOVV 160(R3), R23
+ MOVV 168(R3), R24
+ MOVV 176(R3), R25
+ MOVV 184(R3), R26
+ MOVV 192(R3), R29
+ MOVV 200(R3), R31
+ JMP ret
+
+// Note: these functions use a special calling convention to save generated code space.
+// Arguments are passed in registers, but the space for those arguments are allocated
+// in the caller's stack frame. These stubs write the args into that stack space and
+// then tail call to the corresponding runtime handler.
+// The tail call makes these stubs disappear in backtraces.
+TEXT runtime·panicIndex(SB),NOSPLIT,$0-16
+ MOVV R19, x+0(FP)
+ MOVV R18, y+8(FP)
+ JMP runtime·goPanicIndex(SB)
+TEXT runtime·panicIndexU(SB),NOSPLIT,$0-16
+ MOVV R19, x+0(FP)
+ MOVV R18, y+8(FP)
+ JMP runtime·goPanicIndexU(SB)
+TEXT runtime·panicSliceAlen(SB),NOSPLIT,$0-16
+ MOVV R18, x+0(FP)
+ MOVV R17, y+8(FP)
+ JMP runtime·goPanicSliceAlen(SB)
+TEXT runtime·panicSliceAlenU(SB),NOSPLIT,$0-16
+ MOVV R18, x+0(FP)
+ MOVV R17, y+8(FP)
+ JMP runtime·goPanicSliceAlenU(SB)
+TEXT runtime·panicSliceAcap(SB),NOSPLIT,$0-16
+ MOVV R18, x+0(FP)
+ MOVV R17, y+8(FP)
+ JMP runtime·goPanicSliceAcap(SB)
+TEXT runtime·panicSliceAcapU(SB),NOSPLIT,$0-16
+ MOVV R18, x+0(FP)
+ MOVV R17, y+8(FP)
+ JMP runtime·goPanicSliceAcapU(SB)
+TEXT runtime·panicSliceB(SB),NOSPLIT,$0-16
+ MOVV R19, x+0(FP)
+ MOVV R18, y+8(FP)
+ JMP runtime·goPanicSliceB(SB)
+TEXT runtime·panicSliceBU(SB),NOSPLIT,$0-16
+ MOVV R19, x+0(FP)
+ MOVV R18, y+8(FP)
+ JMP runtime·goPanicSliceBU(SB)
+TEXT runtime·panicSlice3Alen(SB),NOSPLIT,$0-16
+ MOVV R17, x+0(FP)
+ MOVV R4, y+8(FP)
+ JMP runtime·goPanicSlice3Alen(SB)
+TEXT runtime·panicSlice3AlenU(SB),NOSPLIT,$0-16
+ MOVV R17, x+0(FP)
+ MOVV R4, y+8(FP)
+ JMP runtime·goPanicSlice3AlenU(SB)
+TEXT runtime·panicSlice3Acap(SB),NOSPLIT,$0-16
+ MOVV R17, x+0(FP)
+ MOVV R4, y+8(FP)
+ JMP runtime·goPanicSlice3Acap(SB)
+TEXT runtime·panicSlice3AcapU(SB),NOSPLIT,$0-16
+ MOVV R17, x+0(FP)
+ MOVV R4, y+8(FP)
+ JMP runtime·goPanicSlice3AcapU(SB)
+TEXT runtime·panicSlice3B(SB),NOSPLIT,$0-16
+ MOVV R18, x+0(FP)
+ MOVV R17, y+8(FP)
+ JMP runtime·goPanicSlice3B(SB)
+TEXT runtime·panicSlice3BU(SB),NOSPLIT,$0-16
+ MOVV R18, x+0(FP)
+ MOVV R17, y+8(FP)
+ JMP runtime·goPanicSlice3BU(SB)
+TEXT runtime·panicSlice3C(SB),NOSPLIT,$0-16
+ MOVV R19, x+0(FP)
+ MOVV R18, y+8(FP)
+ JMP runtime·goPanicSlice3C(SB)
+TEXT runtime·panicSlice3CU(SB),NOSPLIT,$0-16
+ MOVV R19, x+0(FP)
+ MOVV R18, y+8(FP)
+ JMP runtime·goPanicSlice3CU(SB)
+TEXT runtime·panicSliceConvert(SB),NOSPLIT,$0-16
+ MOVV R17, x+0(FP)
+ MOVV R4, y+8(FP)
+ JMP runtime·goPanicSliceConvert(SB)