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diff --git a/src/runtime/asm_riscv64.s b/src/runtime/asm_riscv64.s
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+// Copyright 2017 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 "funcdata.h"
+#include "textflag.h"
+
+// func rt0_go()
+TEXT runtime·rt0_go(SB),NOSPLIT|TOPFRAME,$0
+ // X2 = stack; A0 = argc; A1 = argv
+ ADD $-24, X2
+ MOV A0, 8(X2) // argc
+ MOV A1, 16(X2) // argv
+
+ // create istack out of the given (operating system) stack.
+ // _cgo_init may update stackguard.
+ MOV $runtime·g0(SB), g
+ MOV $(-64*1024), T0
+ ADD T0, X2, T1
+ MOV T1, g_stackguard0(g)
+ MOV T1, g_stackguard1(g)
+ MOV T1, (g_stack+stack_lo)(g)
+ MOV X2, (g_stack+stack_hi)(g)
+
+ // if there is a _cgo_init, call it using the gcc ABI.
+ MOV _cgo_init(SB), T0
+ BEQ T0, ZERO, nocgo
+
+ MOV ZERO, A3 // arg 3: not used
+ MOV ZERO, A2 // arg 2: not used
+ MOV $setg_gcc<>(SB), A1 // arg 1: setg
+ MOV g, A0 // arg 0: G
+ JALR RA, T0
+
+nocgo:
+ // update stackguard after _cgo_init
+ MOV (g_stack+stack_lo)(g), T0
+ ADD $const_stackGuard, T0
+ MOV T0, g_stackguard0(g)
+ MOV T0, g_stackguard1(g)
+
+ // set the per-goroutine and per-mach "registers"
+ MOV $runtime·m0(SB), T0
+
+ // save m->g0 = g0
+ MOV g, m_g0(T0)
+ // save m0 to g0->m
+ MOV T0, g_m(g)
+
+ CALL runtime·check(SB)
+
+ // args are already prepared
+ CALL runtime·args(SB)
+ CALL runtime·osinit(SB)
+ CALL runtime·schedinit(SB)
+
+ // create a new goroutine to start program
+ MOV $runtime·mainPC(SB), T0 // entry
+ ADD $-16, X2
+ MOV T0, 8(X2)
+ MOV ZERO, 0(X2)
+ CALL runtime·newproc(SB)
+ ADD $16, X2
+
+ // start this M
+ CALL runtime·mstart(SB)
+
+ WORD $0 // crash if reached
+ RET
+
+TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
+ CALL runtime·mstart0(SB)
+ RET // not reached
+
+// void setg_gcc(G*); set g called from gcc with g in A0
+TEXT setg_gcc<>(SB),NOSPLIT,$0-0
+ MOV A0, g
+ CALL runtime·save_g(SB)
+ RET
+
+// func cputicks() int64
+TEXT runtime·cputicks(SB),NOSPLIT,$0-8
+ // RDTIME to emulate cpu ticks
+ // RDCYCLE reads counter that is per HART(core) based
+ // according to the riscv manual, see issue 46737
+ RDTIME A0
+ MOV A0, ret+0(FP)
+ 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
+ UNDEF
+ JALR RA, ZERO // make sure this function is not leaf
+ RET
+
+// func systemstack(fn func())
+TEXT runtime·systemstack(SB), NOSPLIT, $0-8
+ MOV fn+0(FP), CTXT // CTXT = fn
+ MOV g_m(g), T0 // T0 = m
+
+ MOV m_gsignal(T0), T1 // T1 = gsignal
+ BEQ g, T1, noswitch
+
+ MOV m_g0(T0), T1 // T1 = g0
+ BEQ g, T1, noswitch
+
+ MOV m_curg(T0), T2
+ BEQ g, T2, switch
+
+ // Bad: g is not gsignal, not g0, not curg. What is it?
+ // Hide call from linker nosplit analysis.
+ MOV $runtime·badsystemstack(SB), T1
+ JALR RA, T1
+
+switch:
+ // save our state in g->sched. Pretend to
+ // be systemstack_switch if the G stack is scanned.
+ CALL gosave_systemstack_switch<>(SB)
+
+ // switch to g0
+ MOV T1, g
+ CALL runtime·save_g(SB)
+ MOV (g_sched+gobuf_sp)(g), T0
+ MOV T0, X2
+
+ // call target function
+ MOV 0(CTXT), T1 // code pointer
+ JALR RA, T1
+
+ // switch back to g
+ MOV g_m(g), T0
+ MOV m_curg(T0), g
+ CALL runtime·save_g(SB)
+ MOV (g_sched+gobuf_sp)(g), X2
+ MOV ZERO, (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.
+ MOV 0(CTXT), T1 // code pointer
+ ADD $8, X2
+ JMP (T1)
+
+TEXT runtime·getcallerpc(SB),NOSPLIT|NOFRAME,$0-8
+ MOV 0(X2), T0 // LR saved by caller
+ MOV T0, ret+0(FP)
+ RET
+
+/*
+ * support for morestack
+ */
+
+// Called during function prolog when more stack is needed.
+// Called with return address (i.e. caller's PC) in X5 (aka T0),
+// and the LR register contains the caller's 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.
+
+// func morestack()
+TEXT runtime·morestack(SB),NOSPLIT|NOFRAME,$0-0
+ // Cannot grow scheduler stack (m->g0).
+ MOV g_m(g), A0
+ MOV m_g0(A0), A1
+ BNE g, A1, 3(PC)
+ CALL runtime·badmorestackg0(SB)
+ CALL runtime·abort(SB)
+
+ // Cannot grow signal stack (m->gsignal).
+ MOV m_gsignal(A0), A1
+ BNE g, A1, 3(PC)
+ CALL runtime·badmorestackgsignal(SB)
+ CALL runtime·abort(SB)
+
+ // Called from f.
+ // Set g->sched to context in f.
+ MOV X2, (g_sched+gobuf_sp)(g)
+ MOV T0, (g_sched+gobuf_pc)(g)
+ MOV RA, (g_sched+gobuf_lr)(g)
+ MOV CTXT, (g_sched+gobuf_ctxt)(g)
+
+ // Called from f.
+ // Set m->morebuf to f's caller.
+ MOV RA, (m_morebuf+gobuf_pc)(A0) // f's caller's PC
+ MOV X2, (m_morebuf+gobuf_sp)(A0) // f's caller's SP
+ MOV g, (m_morebuf+gobuf_g)(A0)
+
+ // Call newstack on m->g0's stack.
+ MOV m_g0(A0), g
+ CALL runtime·save_g(SB)
+ MOV (g_sched+gobuf_sp)(g), X2
+ // Create a stack frame on g0 to call newstack.
+ MOV ZERO, -8(X2) // Zero saved LR in frame
+ ADD $-8, X2
+ CALL 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
+
+// func morestack_noctxt()
+TEXT runtime·morestack_noctxt(SB),NOSPLIT|NOFRAME,$0-0
+ // Force SPWRITE. This function doesn't actually write SP,
+ // but it is called with a special calling convention where
+ // the caller doesn't save LR on stack but passes it as a
+ // register, and the unwinder currently doesn't understand.
+ // Make it SPWRITE to stop unwinding. (See issue 54332)
+ MOV X2, X2
+
+ MOV ZERO, CTXT
+ JMP runtime·morestack(SB)
+
+// AES hashing not implemented for riscv64
+TEXT runtime·memhash<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-32
+ JMP runtime·memhashFallback<ABIInternal>(SB)
+TEXT runtime·strhash<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-24
+ JMP runtime·strhashFallback<ABIInternal>(SB)
+TEXT runtime·memhash32<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-24
+ JMP runtime·memhash32Fallback<ABIInternal>(SB)
+TEXT runtime·memhash64<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-24
+ JMP runtime·memhash64Fallback<ABIInternal>(SB)
+
+// func return0()
+TEXT runtime·return0(SB), NOSPLIT, $0
+ MOV $0, A0
+ RET
+
+// restore state from Gobuf; longjmp
+
+// func gogo(buf *gobuf)
+TEXT runtime·gogo(SB), NOSPLIT|NOFRAME, $0-8
+ MOV buf+0(FP), T0
+ MOV gobuf_g(T0), T1
+ MOV 0(T1), ZERO // make sure g != nil
+ JMP gogo<>(SB)
+
+TEXT gogo<>(SB), NOSPLIT|NOFRAME, $0
+ MOV T1, g
+ CALL runtime·save_g(SB)
+
+ MOV gobuf_sp(T0), X2
+ MOV gobuf_lr(T0), RA
+ MOV gobuf_ret(T0), A0
+ MOV gobuf_ctxt(T0), CTXT
+ MOV ZERO, gobuf_sp(T0)
+ MOV ZERO, gobuf_ret(T0)
+ MOV ZERO, gobuf_lr(T0)
+ MOV ZERO, gobuf_ctxt(T0)
+ MOV gobuf_pc(T0), T0
+ JALR ZERO, T0
+
+// func procyield(cycles uint32)
+TEXT runtime·procyield(SB),NOSPLIT,$0-0
+ RET
+
+// Switch to m->g0's stack, call fn(g).
+// Fn must never return. It should gogo(&g->sched)
+// to keep running g.
+
+// func mcall(fn func(*g))
+TEXT runtime·mcall<ABIInternal>(SB), NOSPLIT|NOFRAME, $0-8
+ MOV X10, CTXT
+
+ // Save caller state in g->sched
+ MOV X2, (g_sched+gobuf_sp)(g)
+ MOV RA, (g_sched+gobuf_pc)(g)
+ MOV ZERO, (g_sched+gobuf_lr)(g)
+
+ // Switch to m->g0 & its stack, call fn.
+ MOV g, X10
+ MOV g_m(g), T1
+ MOV m_g0(T1), g
+ CALL runtime·save_g(SB)
+ BNE g, X10, 2(PC)
+ JMP runtime·badmcall(SB)
+ MOV 0(CTXT), T1 // code pointer
+ MOV (g_sched+gobuf_sp)(g), X2 // sp = m->g0->sched.sp
+ // we don't need special macro for regabi since arg0(X10) = g
+ ADD $-16, X2
+ MOV X10, 8(X2) // setup g
+ MOV ZERO, 0(X2) // clear return address
+ JALR RA, T1
+ JMP runtime·badmcall2(SB)
+
+// 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 X31.
+TEXT gosave_systemstack_switch<>(SB),NOSPLIT|NOFRAME,$0
+ MOV $runtime·systemstack_switch(SB), X31
+ ADD $8, X31 // get past prologue
+ MOV X31, (g_sched+gobuf_pc)(g)
+ MOV X2, (g_sched+gobuf_sp)(g)
+ MOV ZERO, (g_sched+gobuf_lr)(g)
+ MOV ZERO, (g_sched+gobuf_ret)(g)
+ // Assert ctxt is zero. See func save.
+ MOV (g_sched+gobuf_ctxt)(g), X31
+ BEQ ZERO, X31, 2(PC)
+ CALL 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
+ MOV fn+0(FP), X5
+ MOV arg+8(FP), X10
+
+ MOV X2, X8 // save original stack pointer
+ MOV g, X9
+
+ // 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. Or we might already
+ // be on the m->gsignal stack.
+ MOV g_m(g), X6
+ MOV m_gsignal(X6), X7
+ BEQ X7, g, g0
+ MOV m_g0(X6), X7
+ BEQ X7, g, g0
+
+ CALL gosave_systemstack_switch<>(SB)
+ MOV X7, g
+ CALL runtime·save_g(SB)
+ MOV (g_sched+gobuf_sp)(g), X2
+
+ // Now on a scheduling stack (a pthread-created stack).
+g0:
+ // Save room for two of our pointers.
+ ADD $-16, X2
+ MOV X9, 0(X2) // save old g on stack
+ MOV (g_stack+stack_hi)(X9), X9
+ SUB X8, X9, X8
+ MOV X8, 8(X2) // save depth in old g stack (can't just save SP, as stack might be copied during a callback)
+
+ JALR RA, (X5)
+
+ // Restore g, stack pointer. X10 is return value.
+ MOV 0(X2), g
+ CALL runtime·save_g(SB)
+ MOV (g_stack+stack_hi)(g), X5
+ MOV 8(X2), X6
+ SUB X6, X5, X6
+ MOV X6, X2
+
+ MOVW X10, ret+16(FP)
+ RET
+
+// func asminit()
+TEXT runtime·asminit(SB),NOSPLIT|NOFRAME,$0-0
+ RET
+
+// reflectcall: call a function with the given argument list
+// func call(stackArgsType *_type, f *FuncVal, stackArgs *byte, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs).
+// 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) \
+ MOV $MAXSIZE, T1 \
+ BLTU T1, T0, 3(PC) \
+ MOV $NAME(SB), T2; \
+ JALR ZERO, T2
+// Note: can't just "BR NAME(SB)" - bad inlining results.
+
+// func call(stackArgsType *rtype, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs).
+TEXT reflect·call(SB), NOSPLIT, $0-0
+ JMP ·reflectcall(SB)
+
+// func call(stackArgsType *_type, fn, stackArgs unsafe.Pointer, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs).
+TEXT ·reflectcall(SB), NOSPLIT|NOFRAME, $0-48
+ MOVWU frameSize+32(FP), T0
+ 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)
+ MOV $runtime·badreflectcall(SB), T2
+ JALR ZERO, T2
+
+#define CALLFN(NAME,MAXSIZE) \
+TEXT NAME(SB), WRAPPER, $MAXSIZE-48; \
+ NO_LOCAL_POINTERS; \
+ /* copy arguments to stack */ \
+ MOV stackArgs+16(FP), A1; \
+ MOVWU stackArgsSize+24(FP), A2; \
+ MOV X2, A3; \
+ ADD $8, A3; \
+ ADD A3, A2; \
+ BEQ A3, A2, 6(PC); \
+ MOVBU (A1), A4; \
+ ADD $1, A1; \
+ MOVB A4, (A3); \
+ ADD $1, A3; \
+ JMP -5(PC); \
+ /* set up argument registers */ \
+ MOV regArgs+40(FP), X25; \
+ CALL ·unspillArgs(SB); \
+ /* call function */ \
+ MOV f+8(FP), CTXT; \
+ MOV (CTXT), X25; \
+ PCDATA $PCDATA_StackMapIndex, $0; \
+ JALR RA, X25; \
+ /* copy return values back */ \
+ MOV regArgs+40(FP), X25; \
+ CALL ·spillArgs(SB); \
+ MOV stackArgsType+0(FP), A5; \
+ MOV stackArgs+16(FP), A1; \
+ MOVWU stackArgsSize+24(FP), A2; \
+ MOVWU stackRetOffset+28(FP), A4; \
+ ADD $8, X2, A3; \
+ ADD A4, A3; \
+ ADD A4, A1; \
+ SUB A4, A2; \
+ 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
+ MOV A5, 8(X2)
+ MOV A1, 16(X2)
+ MOV A3, 24(X2)
+ MOV A2, 32(X2)
+ MOV X25, 40(X2)
+ 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)
+
+// Called from cgo wrappers, this function returns g->m->curg.stack.hi.
+// Must obey the gcc calling convention.
+TEXT _cgo_topofstack(SB),NOSPLIT,$8
+ // g (X27) and REG_TMP (X31) might be clobbered by load_g.
+ // X27 is callee-save in the gcc calling convention, so save it.
+ MOV g, savedX27-8(SP)
+
+ CALL runtime·load_g(SB)
+ MOV g_m(g), X5
+ MOV m_curg(X5), X5
+ MOV (g_stack+stack_hi)(X5), X10 // return value in X10
+
+ MOV savedX27-8(SP), g
+ RET
+
+// func goexit(neverCallThisFunction)
+// The top-most function running on a goroutine
+// returns to goexit+PCQuantum.
+TEXT runtime·goexit(SB),NOSPLIT|NOFRAME|TOPFRAME,$0-0
+ MOV ZERO, ZERO // NOP
+ JMP runtime·goexit1(SB) // does not return
+ // traceback from goexit1 must hit code range of goexit
+ MOV ZERO, ZERO // NOP
+
+// func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
+// See cgocall.go for more details.
+TEXT ·cgocallback(SB),NOSPLIT,$24-24
+ NO_LOCAL_POINTERS
+
+ // Skip cgocallbackg, just dropm when fn is nil, and frame is the saved g.
+ // It is used to dropm while thread is exiting.
+ MOV fn+0(FP), X7
+ BNE ZERO, X7, loadg
+ // Restore the g from frame.
+ MOV frame+8(FP), g
+ JMP dropm
+
+loadg:
+ // Load m and g from thread-local storage.
+ MOVBU runtime·iscgo(SB), X5
+ BEQ ZERO, X5, nocgo
+ CALL runtime·load_g(SB)
+nocgo:
+
+ // If g is nil, Go did not create the current thread,
+ // or if this thread never called into Go on pthread platforms.
+ // 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 ZERO, g, needm
+
+ MOV g_m(g), X5
+ MOV X5, savedm-8(SP)
+ JMP havem
+
+needm:
+ MOV g, savedm-8(SP) // g is zero, so is m.
+ MOV $runtime·needAndBindM(SB), X6
+ JALR RA, X6
+
+ // 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.
+ MOV g_m(g), X5
+ MOV m_g0(X5), X6
+ MOV X2, (g_sched+gobuf_sp)(X6)
+
+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(X2) aka savedsp-24(SP).
+ MOV m_g0(X5), X6
+ MOV (g_sched+gobuf_sp)(X6), X7
+ MOV X7, savedsp-24(SP) // must match frame size
+ MOV X2, (g_sched+gobuf_sp)(X6)
+
+ // 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 curg stack and
+ // open a frame the same size as cgocallback's g0 frame.
+ // Once we switch to the curg stack, the pushed PC will appear
+ // to be the return PC of cgocallback, so that the traceback
+ // will seamlessly trace back into the earlier calls.
+ MOV m_curg(X5), g
+ CALL runtime·save_g(SB)
+ MOV (g_sched+gobuf_sp)(g), X6 // prepare stack as X6
+ MOV (g_sched+gobuf_pc)(g), X7
+ MOV X7, -(24+8)(X6) // "saved LR"; must match frame size
+ // Gather our arguments into registers.
+ MOV fn+0(FP), X7
+ MOV frame+8(FP), X8
+ MOV ctxt+16(FP), X9
+ MOV $-(24+8)(X6), X2 // switch stack; must match frame size
+ MOV X7, 8(X2)
+ MOV X8, 16(X2)
+ MOV X9, 24(X2)
+ CALL runtime·cgocallbackg(SB)
+
+ // Restore g->sched (== m->curg->sched) from saved values.
+ MOV 0(X2), X7
+ MOV X7, (g_sched+gobuf_pc)(g)
+ MOV $(24+8)(X2), X6 // must match frame size
+ MOV X6, (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.)
+ MOV g_m(g), X5
+ MOV m_g0(X5), g
+ CALL runtime·save_g(SB)
+ MOV (g_sched+gobuf_sp)(g), X2
+ MOV savedsp-24(SP), X6 // must match frame size
+ MOV X6, (g_sched+gobuf_sp)(g)
+
+ // If the m on entry was nil, we called needm above to borrow an m,
+ // 1. for the duration of the call on non-pthread platforms,
+ // 2. or the duration of the C thread alive on pthread platforms.
+ // If the m on entry wasn't nil,
+ // 1. the thread might be a Go thread,
+ // 2. or it wasn't the first call from a C thread on pthread platforms,
+ // since then we skip dropm to reuse the m in the first call.
+ MOV savedm-8(SP), X5
+ BNE ZERO, X5, droppedm
+
+ // Skip dropm to reuse it in the next call, when a pthread key has been created.
+ MOV _cgo_pthread_key_created(SB), X5
+ // It means cgo is disabled when _cgo_pthread_key_created is a nil pointer, need dropm.
+ BEQ ZERO, X5, dropm
+ MOV (X5), X5
+ BNE ZERO, X5, droppedm
+
+dropm:
+ MOV $runtime·dropm(SB), X6
+ JALR RA, X6
+droppedm:
+
+ // Done!
+ RET
+
+TEXT runtime·breakpoint(SB),NOSPLIT|NOFRAME,$0-0
+ EBREAK
+ RET
+
+TEXT runtime·abort(SB),NOSPLIT|NOFRAME,$0-0
+ EBREAK
+ RET
+
+// void setg(G*); set g. for use by needm.
+TEXT runtime·setg(SB), NOSPLIT, $0-8
+ MOV gg+0(FP), g
+ // This only happens if iscgo, so jump straight to save_g
+ CALL runtime·save_g(SB)
+ RET
+
+TEXT ·checkASM(SB),NOSPLIT,$0-1
+ MOV $1, T0
+ MOV T0, ret+0(FP)
+ RET
+
+// spillArgs stores return values from registers to a *internal/abi.RegArgs in X25.
+TEXT ·spillArgs(SB),NOSPLIT,$0-0
+ MOV X10, (0*8)(X25)
+ MOV X11, (1*8)(X25)
+ MOV X12, (2*8)(X25)
+ MOV X13, (3*8)(X25)
+ MOV X14, (4*8)(X25)
+ MOV X15, (5*8)(X25)
+ MOV X16, (6*8)(X25)
+ MOV X17, (7*8)(X25)
+ MOV X8, (8*8)(X25)
+ MOV X9, (9*8)(X25)
+ MOV X18, (10*8)(X25)
+ MOV X19, (11*8)(X25)
+ MOV X20, (12*8)(X25)
+ MOV X21, (13*8)(X25)
+ MOV X22, (14*8)(X25)
+ MOV X23, (15*8)(X25)
+ MOVD F10, (16*8)(X25)
+ MOVD F11, (17*8)(X25)
+ MOVD F12, (18*8)(X25)
+ MOVD F13, (19*8)(X25)
+ MOVD F14, (20*8)(X25)
+ MOVD F15, (21*8)(X25)
+ MOVD F16, (22*8)(X25)
+ MOVD F17, (23*8)(X25)
+ MOVD F8, (24*8)(X25)
+ MOVD F9, (25*8)(X25)
+ MOVD F18, (26*8)(X25)
+ MOVD F19, (27*8)(X25)
+ MOVD F20, (28*8)(X25)
+ MOVD F21, (29*8)(X25)
+ MOVD F22, (30*8)(X25)
+ MOVD F23, (31*8)(X25)
+ RET
+
+// unspillArgs loads args into registers from a *internal/abi.RegArgs in X25.
+TEXT ·unspillArgs(SB),NOSPLIT,$0-0
+ MOV (0*8)(X25), X10
+ MOV (1*8)(X25), X11
+ MOV (2*8)(X25), X12
+ MOV (3*8)(X25), X13
+ MOV (4*8)(X25), X14
+ MOV (5*8)(X25), X15
+ MOV (6*8)(X25), X16
+ MOV (7*8)(X25), X17
+ MOV (8*8)(X25), X8
+ MOV (9*8)(X25), X9
+ MOV (10*8)(X25), X18
+ MOV (11*8)(X25), X19
+ MOV (12*8)(X25), X20
+ MOV (13*8)(X25), X21
+ MOV (14*8)(X25), X22
+ MOV (15*8)(X25), X23
+ MOVD (16*8)(X25), F10
+ MOVD (17*8)(X25), F11
+ MOVD (18*8)(X25), F12
+ MOVD (19*8)(X25), F13
+ MOVD (20*8)(X25), F14
+ MOVD (21*8)(X25), F15
+ MOVD (22*8)(X25), F16
+ MOVD (23*8)(X25), F17
+ MOVD (24*8)(X25), F8
+ MOVD (25*8)(X25), F9
+ MOVD (26*8)(X25), F18
+ MOVD (27*8)(X25), F19
+ MOVD (28*8)(X25), F20
+ MOVD (29*8)(X25), F21
+ MOVD (30*8)(X25), F22
+ MOVD (31*8)(X25), F23
+ RET
+
+// gcWriteBarrier informs the GC about heap pointer writes.
+//
+// gcWriteBarrier does NOT follow the Go ABI. It accepts the
+// number of bytes of buffer needed in X24, and returns a pointer
+// to the buffer space in X24.
+// It clobbers X31 aka T6 (the linker temp register - REG_TMP).
+// The act of CALLing gcWriteBarrier will clobber RA (LR).
+// It does not clobber any other general-purpose registers,
+// but may clobber others (e.g., floating point registers).
+TEXT gcWriteBarrier<>(SB),NOSPLIT,$208
+ // Save the registers clobbered by the fast path.
+ MOV A0, 24*8(X2)
+ MOV A1, 25*8(X2)
+retry:
+ MOV g_m(g), A0
+ MOV m_p(A0), A0
+ MOV (p_wbBuf+wbBuf_next)(A0), A1
+ MOV (p_wbBuf+wbBuf_end)(A0), T6 // T6 is linker temp register (REG_TMP)
+ // Increment wbBuf.next position.
+ ADD X24, A1
+ // Is the buffer full?
+ BLTU T6, A1, flush
+ // Commit to the larger buffer.
+ MOV A1, (p_wbBuf+wbBuf_next)(A0)
+ // Make the return value (the original next position)
+ SUB X24, A1, X24
+ // Restore registers.
+ MOV 24*8(X2), A0
+ MOV 25*8(X2), A1
+ RET
+
+flush:
+ // Save all general purpose registers since these could be
+ // clobbered by wbBufFlush and were not saved by the caller.
+ MOV T0, 1*8(X2)
+ MOV T1, 2*8(X2)
+ // X0 is zero register
+ // X1 is LR, saved by prologue
+ // X2 is SP
+ // X3 is GP
+ // X4 is TP
+ MOV X7, 3*8(X2)
+ MOV X8, 4*8(X2)
+ MOV X9, 5*8(X2)
+ // X10 already saved (A0)
+ // X11 already saved (A1)
+ MOV X12, 6*8(X2)
+ MOV X13, 7*8(X2)
+ MOV X14, 8*8(X2)
+ MOV X15, 9*8(X2)
+ MOV X16, 10*8(X2)
+ MOV X17, 11*8(X2)
+ MOV X18, 12*8(X2)
+ MOV X19, 13*8(X2)
+ MOV X20, 14*8(X2)
+ MOV X21, 15*8(X2)
+ MOV X22, 16*8(X2)
+ MOV X23, 17*8(X2)
+ MOV X24, 18*8(X2)
+ MOV X25, 19*8(X2)
+ MOV X26, 20*8(X2)
+ // X27 is g.
+ MOV X28, 21*8(X2)
+ MOV X29, 22*8(X2)
+ MOV X30, 23*8(X2)
+ // X31 is tmp register.
+
+ CALL runtime·wbBufFlush(SB)
+
+ MOV 1*8(X2), T0
+ MOV 2*8(X2), T1
+ MOV 3*8(X2), X7
+ MOV 4*8(X2), X8
+ MOV 5*8(X2), X9
+ MOV 6*8(X2), X12
+ MOV 7*8(X2), X13
+ MOV 8*8(X2), X14
+ MOV 9*8(X2), X15
+ MOV 10*8(X2), X16
+ MOV 11*8(X2), X17
+ MOV 12*8(X2), X18
+ MOV 13*8(X2), X19
+ MOV 14*8(X2), X20
+ MOV 15*8(X2), X21
+ MOV 16*8(X2), X22
+ MOV 17*8(X2), X23
+ MOV 18*8(X2), X24
+ MOV 19*8(X2), X25
+ MOV 20*8(X2), X26
+ MOV 21*8(X2), X28
+ MOV 22*8(X2), X29
+ MOV 23*8(X2), X30
+
+ JMP retry
+
+TEXT runtime·gcWriteBarrier1<ABIInternal>(SB),NOSPLIT,$0
+ MOV $8, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier2<ABIInternal>(SB),NOSPLIT,$0
+ MOV $16, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier3<ABIInternal>(SB),NOSPLIT,$0
+ MOV $24, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier4<ABIInternal>(SB),NOSPLIT,$0
+ MOV $32, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier5<ABIInternal>(SB),NOSPLIT,$0
+ MOV $40, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier6<ABIInternal>(SB),NOSPLIT,$0
+ MOV $48, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier7<ABIInternal>(SB),NOSPLIT,$0
+ MOV $56, X24
+ JMP gcWriteBarrier<>(SB)
+TEXT runtime·gcWriteBarrier8<ABIInternal>(SB),NOSPLIT,$0
+ MOV $64, X24
+ JMP gcWriteBarrier<>(SB)
+
+// Note: these functions use a special calling convention to save generated code space.
+// Arguments are passed in registers (ssa/gen/RISCV64Ops.go), 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<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T0, X10
+ MOV T1, X11
+ JMP runtime·goPanicIndex<ABIInternal>(SB)
+TEXT runtime·panicIndexU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T0, X10
+ MOV T1, X11
+ JMP runtime·goPanicIndexU<ABIInternal>(SB)
+TEXT runtime·panicSliceAlen<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T1, X10
+ MOV T2, X11
+ JMP runtime·goPanicSliceAlen<ABIInternal>(SB)
+TEXT runtime·panicSliceAlenU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T1, X10
+ MOV T2, X11
+ JMP runtime·goPanicSliceAlenU<ABIInternal>(SB)
+TEXT runtime·panicSliceAcap<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T1, X10
+ MOV T2, X11
+ JMP runtime·goPanicSliceAcap<ABIInternal>(SB)
+TEXT runtime·panicSliceAcapU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T1, X10
+ MOV T2, X11
+ JMP runtime·goPanicSliceAcapU<ABIInternal>(SB)
+TEXT runtime·panicSliceB<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T0, X10
+ MOV T1, X11
+ JMP runtime·goPanicSliceB<ABIInternal>(SB)
+TEXT runtime·panicSliceBU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T0, X10
+ MOV T1, X11
+ JMP runtime·goPanicSliceBU<ABIInternal>(SB)
+TEXT runtime·panicSlice3Alen<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T2, X10
+ MOV T3, X11
+ JMP runtime·goPanicSlice3Alen<ABIInternal>(SB)
+TEXT runtime·panicSlice3AlenU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T2, X10
+ MOV T3, X11
+ JMP runtime·goPanicSlice3AlenU<ABIInternal>(SB)
+TEXT runtime·panicSlice3Acap<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T2, X10
+ MOV T3, X11
+ JMP runtime·goPanicSlice3Acap<ABIInternal>(SB)
+TEXT runtime·panicSlice3AcapU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T2, X10
+ MOV T3, X11
+ JMP runtime·goPanicSlice3AcapU<ABIInternal>(SB)
+TEXT runtime·panicSlice3B<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T1, X10
+ MOV T2, X11
+ JMP runtime·goPanicSlice3B<ABIInternal>(SB)
+TEXT runtime·panicSlice3BU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T1, X10
+ MOV T2, X11
+ JMP runtime·goPanicSlice3BU<ABIInternal>(SB)
+TEXT runtime·panicSlice3C<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T0, X10
+ MOV T1, X11
+ JMP runtime·goPanicSlice3C<ABIInternal>(SB)
+TEXT runtime·panicSlice3CU<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T0, X10
+ MOV T1, X11
+ JMP runtime·goPanicSlice3CU<ABIInternal>(SB)
+TEXT runtime·panicSliceConvert<ABIInternal>(SB),NOSPLIT,$0-16
+ MOV T2, X10
+ MOV T3, X11
+ JMP runtime·goPanicSliceConvert<ABIInternal>(SB)
+
+DATA runtime·mainPC+0(SB)/8,$runtime·main<ABIInternal>(SB)
+GLOBL runtime·mainPC(SB),RODATA,$8