blob: 49610451a6f73c9d4f01eea74db5e3321f5fcaf9 [file] [log] [blame]
// Copyright 2009 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 "arm/asm.h"
// using frame size $-4 means do not save LR on stack.
TEXT _rt0_arm(SB),7,$-4
MOVW $setR12(SB), R12
// copy arguments forward on an even stack
// use R13 instead of SP to avoid linker rewriting the offsets
MOVW 0(R13), R0 // argc
MOVW $4(R13), R1 // argv
SUB $128, R13 // plenty of scratch
AND $~7, R13
MOVW R0, 120(R13) // save argc, argv away
MOVW R1, 124(R13)
// set up m and g registers
// g is R10, m is R9
MOVW $g0(SB), g
MOVW $m0(SB), m
// save m->g0 = g0
MOVW g, m_g0(m)
// create istack out of the OS stack
MOVW $(-8192+104)(R13), R0
MOVW R0, g_stackguard(g) // (w 104b guard)
MOVW R13, g_stackbase(g)
BL emptyfunc(SB) // fault if stack check is wrong
BL check(SB)
// saved argc, argv
MOVW 120(R13), R0
MOVW R0, 4(R13)
MOVW 124(R13), R1
MOVW R1, 8(R13)
BL args(SB)
BL osinit(SB)
BL schedinit(SB)
// create a new goroutine to start program
MOVW $mainstart(SB), R0
MOVW.W R0, -4(R13)
MOVW $8, R0
MOVW.W R0, -4(R13)
MOVW $0, R0
MOVW.W R0, -4(R13) // push $0 as guard
BL ·newproc(SB)
MOVW $12(R13), R13 // pop args and LR
// start this M
BL mstart(SB)
MOVW $1234, R0
MOVW $1000, R1
MOVW R0, (R1) // fail hard
B _dep_dummy(SB) // Never reached
TEXT mainstart(SB),7,$4
BL main·init(SB)
BL initdone(SB)
BL main·main(SB)
MOVW $0, R0
MOVW R0, 4(SP)
BL exit(SB)
MOVW $1234, R0
MOVW $1001, R1
MOVW R0, (R1) // fail hard
RET
// TODO(kaib): remove these once i actually understand how the linker removes symbols
// pull in dummy dependencies
TEXT _dep_dummy(SB),7,$0
BL _div(SB)
BL _divu(SB)
BL _mod(SB)
BL _modu(SB)
BL _modu(SB)
BL _sfloat(SB)
TEXT breakpoint(SB),7,$0
BL abort(SB)
// BYTE $0xcc
// RET
/*
* go-routine
*/
// uintptr gosave(Gobuf*)
// save state in Gobuf; setjmp
TEXT gosave(SB), 7, $-4
MOVW 0(FP), R0
MOVW SP, gobuf_sp(R0)
MOVW LR, gobuf_pc(R0)
MOVW g, gobuf_g(R0)
MOVW $0, R0 // return 0
RET
// void gogo(Gobuf*, uintptr)
// restore state from Gobuf; longjmp
TEXT gogo(SB), 7, $-4
MOVW 0(FP), R1 // gobuf
MOVW 4(FP), R0 // return 2nd arg
MOVW gobuf_g(R1), g
MOVW 0(g), R2 // make sure g != nil
MOVW gobuf_sp(R1), SP // restore SP
MOVW gobuf_pc(R1), PC
// void gogocall(Gobuf*, void (*fn)(void))
// restore state from Gobuf but then call fn.
// (call fn, returning to state in Gobuf)
// using frame size $-4 means do not save LR on stack.
TEXT gogocall(SB), 7, $-4
MOVW 0(FP), R0
MOVW 4(FP), R1 // fn
MOVW gobuf_g(R0), g
MOVW 0(g), R2 // make sure g != nil
MOVW gobuf_sp(R0), SP // restore SP
MOVW gobuf_pc(R0), LR
MOVW R1, PC
/*
* support for morestack
*/
// Called during function prolog when more stack is needed.
// R1 frame size
// R2 arg size
// R3 prolog's LR
// NB. we do not save R0 because the we've forced 5c to pass all arguments
// on the stack.
// using frame size $-4 means do not save LR on stack.
TEXT ·morestack(SB),7,$-4
// Cannot grow scheduler stack (m->g0).
MOVW m_g0(m), R4
CMP g, R4
BNE 2(PC)
BL abort(SB)
// Save in m.
MOVW R1, m_moreframe(m)
MOVW R2, m_moreargs(m)
// Called from f.
// Set m->morebuf to f's caller.
MOVW R3, (m_morebuf+gobuf_pc)(m) // f's caller's PC
MOVW SP, (m_morebuf+gobuf_sp)(m) // f's caller's SP
MOVW SP, m_morefp(m) // f's caller's SP
MOVW g, (m_morebuf+gobuf_g)(m)
// Set m->morepc to f's PC.
MOVW LR, m_morepc(m)
// Call newstack on m's scheduling stack.
MOVW m_g0(m), g
MOVW (m_sched+gobuf_sp)(m), SP
B newstack(SB)
// Called from reflection library. Mimics morestack,
// reuses stack growth code to create a frame
// with the desired args running the desired function.
//
// func call(fn *byte, arg *byte, argsize uint32).
TEXT reflect·call(SB), 7, $-4
// Save our caller's state as the PC and SP to
// restore when returning from f.
MOVW LR, (m_morebuf+gobuf_pc)(m) // our caller's PC
MOVW SP, (m_morebuf+gobuf_sp)(m) // our caller's SP
MOVW g, (m_morebuf+gobuf_g)(m)
// Set up morestack arguments to call f on a new stack.
// We set f's frame size to 1, as a hint to newstack
// that this is a call from reflect·call.
// If it turns out that f needs a larger frame than
// the default stack, f's usual stack growth prolog will
// allocate a new segment (and recopy the arguments).
MOVW 4(SP), R0 // fn
MOVW 8(SP), R1 // arg frame
MOVW 12(SP), R2 // arg size
MOVW R0, m_morepc(m) // f's PC
MOVW R1, m_morefp(m) // argument frame pointer
MOVW R2, m_moreargs(m) // f's argument size
MOVW $1, R3
MOVW R3, m_moreframe(m) // f's frame size
// Call newstack on m's scheduling stack.
MOVW m_g0(m), g
MOVW (m_sched+gobuf_sp)(m), SP
B newstack(SB)
// Return point when leaving stack.
// using frame size $-4 means do not save LR on stack.
TEXT ·lessstack(SB), 7, $-4
// Save return value in m->cret
MOVW R0, m_cret(m)
// Call oldstack on m's scheduling stack.
MOVW m_g0(m), g
MOVW (m_sched+gobuf_sp)(m), SP
B oldstack(SB)
// void jmpdefer(fn, sp);
// called from deferreturn.
// 1. grab stored LR for caller
// 2. sub 4 bytes to get back to BL deferreturn
// 3. B to fn
TEXT jmpdefer(SB), 7, $0
MOVW 0(SP), LR
MOVW $-4(LR), LR // BL deferreturn
MOVW 4(SP), R0 // fn
MOVW 8(SP), R1
MOVW $-4(R1), SP // correct for sp pointing to arg0, past stored lr
B (R0)
TEXT ·memclr(SB),7,$20
MOVW 0(FP), R0
MOVW $0, R1 // c = 0
MOVW R1, -16(SP)
MOVW 4(FP), R1 // n
MOVW R1, -12(SP)
MOVW m, -8(SP) // Save m and g
MOVW g, -4(SP)
BL memset(SB)
MOVW -8(SP), m // Restore m and g, memset clobbers them
MOVW -4(SP), g
RET
TEXT ·getcallerpc+0(SB),7,$-4
MOVW 0(SP), R0
RET
TEXT ·setcallerpc+0(SB),7,$-4
MOVW x+4(FP), R0
MOVW R0, 0(SP)
RET
// runcgo(void(*fn)(void*), void *arg)
// Just call fn(arg), but first align the stack
// appropriately for the gcc ABI.
// TODO(kaib): figure out the arm-gcc ABI
TEXT runcgo(SB),7,$16
BL abort(SB)
// MOVL fn+0(FP), AX
// MOVL arg+4(FP), BX
// MOVL SP, CX
// ANDL $~15, SP // alignment for gcc ABI
// MOVL CX, 4(SP)
// MOVL BX, 0(SP)
// CALL AX
// MOVL 4(SP), SP
// RET
TEXT emptyfunc(SB),0,$0
RET
TEXT abort(SB),7,$0
MOVW $0, R0
MOVW (R0), R1
// callString(f, arg, out)
// call Go f(arg), which returns a string, and store in out
TEXT callString(SB), 7, $24
MOVW arg+4(FP), R1
MOVW f+0(FP), R0
MOVW R1, 0(SP)
BL (R0)
MOVW 4(SP), R1
MOVW 8(SP), R2
MOVW 12(SP), R3
MOVW out+8(FP), R0
MOVW R1, 0(R0)
MOVW R2, 4(R0)
MOVW R3, 8(R0)
RET