| // 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 sys·newproc(SB) |
| MOVW $12(R13), R13 // pop args and LR |
| |
| // start this M |
| BL mstart(SB) |
| |
| MOVW $0, R0 |
| SWI $0x00900001 |
| B _dep_dummy(SB) // Never reached |
| |
| |
| TEXT mainstart(SB),7,$0 |
| BL main·init(SB) |
| BL initdone(SB) |
| BL main·main(SB) |
| MOVW $0, R0 |
| MOVW.W R0, -4(SP) |
| MOVW.W R14, -4(SP) // Push link as well |
| BL exit(SB) |
| MOVW $8(SP), SP // pop args and LR |
| RET |
| |
| // TODO(kaib): remove these once linker works properly |
| // 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) |
| |
| 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, $0 |
| 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, $0 |
| MOVW R0, R1 // gobuf |
| MOVW 8(SP), 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 8(SP), 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 gobuf_r0(R0), R0 |
| 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 |
| // using frame size $-4 means do not save LR on stack. |
| TEXT sys·morestack(SB),7,$-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) |
| MOVW R0, (m_morebuf+gobuf_r0)(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 R0, (m_morebuf+gobuf_r0)(m) |
| 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 zero, meaning |
| // allocate a standard sized stack segment. |
| // If it turns out that f needs a larger frame than this, |
| // 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 $0, 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 sys·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) |
| |
| // Optimization to make inline stack splitting code smaller |
| // R0 is original first argument |
| // R2 is argsize |
| // R3 is LR for f (f's caller's PC) |
| // using frame size $-4 means do not save LR on stack. |
| TEXT sys·morestackx(SB), 7, $-4 |
| MOVW $0, R1 // set frame size |
| B sys·morestack(SB) |
| |
| // bool cas(int32 *val, int32 old, int32 new) |
| // Atomically: |
| // if(*val == old){ |
| // *val = new; |
| // return 1; |
| // }else |
| // return 0; |
| #define LDREX(a,r) WORD $(0xe<<28|0x01900f9f | (a)<<16 | (r)<<12) |
| #define STREX(a,v,r) WORD $(0xe<<28|0x01800f90 | (a)<<16 | (r)<<12 | (v)<<0) |
| |
| TEXT cas+0(SB),0,$12 /* r0 holds p */ |
| MOVW ov+4(FP), R1 |
| MOVW nv+8(FP), R2 |
| spin: |
| /* LDREX 0(R0),R3 */ |
| LDREX(0,3) |
| CMP.S R3, R1 |
| BNE fail |
| /* STREX 0(R0),R2,R4 */ |
| STREX(0,2,4) |
| CMP.S $0, R4 |
| BNE spin |
| MOVW $1, R0 |
| RET |
| fail: |
| MOVW $0, R0 |
| RET |
| |
| // void jmpdefer(fn, sp); |
| // called from deferreturn. |
| // 1. pop the caller |
| // 2. sub 5 bytes from the callers return |
| // 3. jmp to the argument |
| TEXT jmpdefer(SB), 7, $0 |
| BL abort(SB) |
| // MOVL 4(SP), AX // fn |
| // MOVL 8(SP), BX // caller sp |
| // LEAL -4(BX), SP // caller sp after CALL |
| // SUBL $5, (SP) // return to CALL again |
| // JMP AX // but first run the deferred function |
| |
| TEXT sys·memclr(SB),7,$20 |
| // R0 = addr and passes implicitly to memset |
| 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 sys·getcallerpc+0(SB),7,$0 |
| BL abort(SB) |
| // MOVL x+0(FP),AX // addr of first arg |
| // MOVL -4(AX),AX // get calling pc |
| // RET |
| |
| TEXT sys·setcallerpc+0(SB),7,$0 |
| BL abort(SB) |
| // MOVL x+0(FP),AX // addr of first arg |
| // MOVL x+4(FP), BX |
| // MOVL BX, -4(AX) // set calling pc |
| // RET |
| |
| TEXT emptyfunc(SB),0,$0 |
| RET |
| |
| TEXT abort(SB),7,$0 |
| MOVW $0, R0 |
| MOVW (R0), R1 |
| |