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Diffstat (limited to 'src/runtime/asm_riscv64.s')
| -rw-r--r-- | src/runtime/asm_riscv64.s | 821 |
1 files changed, 821 insertions, 0 deletions
diff --git a/src/runtime/asm_riscv64.s b/src/runtime/asm_riscv64.s new file mode 100644 index 0000000..01b42dc --- /dev/null +++ b/src/runtime/asm_riscv64.s @@ -0,0 +1,821 @@ +// 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,$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 $-24, X2 + MOV T0, 16(X2) + MOV ZERO, 8(X2) + MOV ZERO, 0(X2) + CALL runtime·newproc(SB) + ADD $24, X2 + + // start this M + CALL runtime·mstart(SB) + + WORD $0 // crash if reached + RET + +// 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 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. + MOV $runtime·systemstack_switch(SB), T2 + ADD $8, T2 // get past prologue + MOV T2, (g_sched+gobuf_pc)(g) + MOV X2, (g_sched+gobuf_sp)(g) + MOV ZERO, (g_sched+gobuf_lr)(g) + MOV g, (g_sched+gobuf_g)(g) + + // switch to g0 + MOV T1, g + CALL runtime·save_g(SB) + MOV (g_sched+gobuf_sp)(g), T0 + // make it look like mstart called systemstack on g0, to stop traceback + ADD $-8, T0 + MOV $runtime·mstart(SB), T1 + MOV T1, 0(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. +// Caller has already loaded: +// R1: framesize, R2: argsize, R3: 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 + MOV ZERO, CTXT + JMP runtime·morestack(SB) + +// AES hashing not implemented for riscv64 +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) + +// 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, $16-8 + MOV buf+0(FP), T0 + MOV gobuf_g(T0), g // make sure g is not nil + CALL runtime·save_g(SB) + + MOV (g), ZERO // make sure g is not nil + 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 jmpdefer(fv *funcval, argp uintptr) +// called from deferreturn +// 1. grab stored return address from the caller's frame +// 2. sub 8 bytes to get back to JAL deferreturn +// 3. JMP to fn +TEXT runtime·jmpdefer(SB), NOSPLIT|NOFRAME, $0-16 + MOV 0(X2), RA + ADD $-8, RA + + MOV fv+0(FP), CTXT + MOV argp+8(FP), X2 + ADD $-8, X2 + MOV 0(CTXT), 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(SB), NOSPLIT|NOFRAME, $0-8 + // 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) + MOV g, (g_sched+gobuf_g)(g) + + // Switch to m->g0 & its stack, call fn. + MOV g, T0 + MOV g_m(g), T1 + MOV m_g0(T1), g + CALL runtime·save_g(SB) + BNE g, T0, 2(PC) + JMP runtime·badmcall(SB) + MOV fn+0(FP), CTXT // context + MOV 0(CTXT), T1 // code pointer + MOV (g_sched+gobuf_sp)(g), X2 // sp = m->g0->sched.sp + ADD $-16, X2 + MOV T0, 8(X2) + MOV ZERO, 0(X2) + JALR RA, T1 + JMP runtime·badmcall2(SB) + +// func gosave(buf *gobuf) +// save state in Gobuf; setjmp +TEXT runtime·gosave(SB), NOSPLIT|NOFRAME, $0-8 + MOV buf+0(FP), T1 + MOV X2, gobuf_sp(T1) + MOV RA, gobuf_pc(T1) + MOV g, gobuf_g(T1) + MOV ZERO, gobuf_lr(T1) + MOV ZERO, gobuf_ret(T1) + // Assert ctxt is zero. See func save. + MOV gobuf_ctxt(T1), T1 + BEQ T1, ZERO, 2(PC) + CALL runtime·badctxt(SB) + RET + +// Save state of caller into g->sched. Smashes X31. +TEXT gosave<>(SB),NOSPLIT|NOFRAME,$0 + MOV X1, (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·badctxt(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. + MOV g_m(g), X6 + MOV m_g0(X6), X7 + BEQ X7, g, g0 + + CALL gosave<>(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(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) \ + 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(argtype *rtype, fn, arg unsafe.Pointer, n uint32, retoffset uint32) +TEXT reflect·call(SB), NOSPLIT, $0-0 + JMP ·reflectcall(SB) + +// func reflectcall(argtype *_type, fn, arg unsafe.Pointer, argsize uint32, retoffset uint32) +TEXT ·reflectcall(SB), NOSPLIT|NOFRAME, $0-32 + MOVWU argsize+24(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-24; \ + NO_LOCAL_POINTERS; \ + /* copy arguments to stack */ \ + MOV arg+16(FP), A1; \ + MOVWU argsize+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); \ + /* call function */ \ + MOV f+8(FP), CTXT; \ + MOV (CTXT), A4; \ + PCDATA $PCDATA_StackMapIndex, $0; \ + JALR RA, A4; \ + /* copy return values back */ \ + MOV argtype+0(FP), A5; \ + MOV arg+16(FP), A1; \ + MOVWU n+24(FP), A2; \ + MOVWU retoffset+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, $32-0 + MOV A5, 8(X2) + MOV A1, 16(X2) + MOV A3, 24(X2) + MOV A2, 32(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 + + // 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. + // 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·needm(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 + // for the duration of the call. Since the call is over, return it with dropm. + MOV savedm-8(SP), X5 + BNE ZERO, X5, droppedm + 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 + +// gcWriteBarrier performs a heap pointer write and informs the GC. +// +// gcWriteBarrier does NOT follow the Go ABI. It takes two arguments: +// - T0 is the destination of the write +// - T1 is the value being written at T0. +// It clobbers R30 (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 runtime·gcWriteBarrier(SB),NOSPLIT,$216 + // Save the registers clobbered by the fast path. + MOV A0, 25*8(X2) + MOV A1, 26*8(X2) + MOV g_m(g), A0 + MOV m_p(A0), A0 + MOV (p_wbBuf+wbBuf_next)(A0), A1 + // Increment wbBuf.next position. + ADD $16, A1 + MOV A1, (p_wbBuf+wbBuf_next)(A0) + MOV (p_wbBuf+wbBuf_end)(A0), A0 + MOV A0, T6 // T6 is linker temp register (REG_TMP) + // Record the write. + MOV T1, -16(A1) // Record value + MOV (T0), A0 // TODO: This turns bad writes into bad reads. + MOV A0, -8(A1) // Record *slot + // Is the buffer full? + BEQ A1, T6, flush +ret: + MOV 25*8(X2), A0 + MOV 26*8(X2), A1 + // Do the write. + MOV T1, (T0) + 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) // Also first argument to wbBufFlush + MOV T1, 2*8(X2) // Also second argument to wbBufFlush + // X0 is zero register + // X1 is LR, saved by prologue + // X2 is SP + MOV X3, 3*8(X2) + // X4 is TP + // X5 is first arg to wbBufFlush (T0) + // X6 is second arg to wbBufFlush (T1) + MOV X7, 4*8(X2) + MOV X8, 5*8(X2) + MOV X9, 6*8(X2) + // X10 already saved (A0) + // X11 already saved (A1) + MOV X12, 7*8(X2) + MOV X13, 8*8(X2) + MOV X14, 9*8(X2) + MOV X15, 10*8(X2) + MOV X16, 11*8(X2) + MOV X17, 12*8(X2) + MOV X18, 13*8(X2) + MOV X19, 14*8(X2) + MOV X20, 15*8(X2) + MOV X21, 16*8(X2) + MOV X22, 17*8(X2) + MOV X23, 18*8(X2) + MOV X24, 19*8(X2) + MOV X25, 20*8(X2) + MOV X26, 21*8(X2) + // X27 is g. + MOV X28, 22*8(X2) + MOV X29, 23*8(X2) + MOV X30, 24*8(X2) + // X31 is tmp register. + + // This takes arguments T0 and T1. + CALL runtime·wbBufFlush(SB) + + MOV 1*8(X2), T0 + MOV 2*8(X2), T1 + MOV 3*8(X2), X3 + MOV 4*8(X2), X7 + MOV 5*8(X2), X8 + MOV 6*8(X2), X9 + MOV 7*8(X2), X12 + MOV 8*8(X2), X13 + MOV 9*8(X2), X14 + MOV 10*8(X2), X15 + MOV 11*8(X2), X16 + MOV 12*8(X2), X17 + MOV 13*8(X2), X18 + MOV 14*8(X2), X19 + MOV 15*8(X2), X20 + MOV 16*8(X2), X21 + MOV 17*8(X2), X22 + MOV 18*8(X2), X23 + MOV 19*8(X2), X24 + MOV 20*8(X2), X25 + MOV 21*8(X2), X26 + MOV 22*8(X2), X28 + MOV 23*8(X2), X29 + MOV 24*8(X2), X30 + + 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 + MOV T0, x+0(FP) + MOV T1, y+8(FP) + JMP runtime·goPanicIndex(SB) +TEXT runtime·panicIndexU(SB),NOSPLIT,$0-16 + MOV T0, x+0(FP) + MOV T1, y+8(FP) + JMP runtime·goPanicIndexU(SB) +TEXT runtime·panicSliceAlen(SB),NOSPLIT,$0-16 + MOV T1, x+0(FP) + MOV T2, y+8(FP) + JMP runtime·goPanicSliceAlen(SB) +TEXT runtime·panicSliceAlenU(SB),NOSPLIT,$0-16 + MOV T1, x+0(FP) + MOV T2, y+8(FP) + JMP runtime·goPanicSliceAlenU(SB) +TEXT runtime·panicSliceAcap(SB),NOSPLIT,$0-16 + MOV T1, x+0(FP) + MOV T2, y+8(FP) + JMP runtime·goPanicSliceAcap(SB) +TEXT runtime·panicSliceAcapU(SB),NOSPLIT,$0-16 + MOV T1, x+0(FP) + MOV T2, y+8(FP) + JMP runtime·goPanicSliceAcapU(SB) +TEXT runtime·panicSliceB(SB),NOSPLIT,$0-16 + MOV T0, x+0(FP) + MOV T1, y+8(FP) + JMP runtime·goPanicSliceB(SB) +TEXT runtime·panicSliceBU(SB),NOSPLIT,$0-16 + MOV T0, x+0(FP) + MOV T1, y+8(FP) + JMP runtime·goPanicSliceBU(SB) +TEXT runtime·panicSlice3Alen(SB),NOSPLIT,$0-16 + MOV T2, x+0(FP) + MOV T3, y+8(FP) + JMP runtime·goPanicSlice3Alen(SB) +TEXT runtime·panicSlice3AlenU(SB),NOSPLIT,$0-16 + MOV T2, x+0(FP) + MOV T3, y+8(FP) + JMP runtime·goPanicSlice3AlenU(SB) +TEXT runtime·panicSlice3Acap(SB),NOSPLIT,$0-16 + MOV T2, x+0(FP) + MOV T3, y+8(FP) + JMP runtime·goPanicSlice3Acap(SB) +TEXT runtime·panicSlice3AcapU(SB),NOSPLIT,$0-16 + MOV T2, x+0(FP) + MOV T3, y+8(FP) + JMP runtime·goPanicSlice3AcapU(SB) +TEXT runtime·panicSlice3B(SB),NOSPLIT,$0-16 + MOV T1, x+0(FP) + MOV T2, y+8(FP) + JMP runtime·goPanicSlice3B(SB) +TEXT runtime·panicSlice3BU(SB),NOSPLIT,$0-16 + MOV T1, x+0(FP) + MOV T2, y+8(FP) + JMP runtime·goPanicSlice3BU(SB) +TEXT runtime·panicSlice3C(SB),NOSPLIT,$0-16 + MOV T0, x+0(FP) + MOV T1, y+8(FP) + JMP runtime·goPanicSlice3C(SB) +TEXT runtime·panicSlice3CU(SB),NOSPLIT,$0-16 + MOV T0, x+0(FP) + MOV T1, y+8(FP) + JMP runtime·goPanicSlice3CU(SB) + +DATA runtime·mainPC+0(SB)/8,$runtime·main(SB) +GLOBL runtime·mainPC(SB),RODATA,$8 |