| // Copyright 2016 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" |
| |
| // _rt0_s390x_lib is common startup code for s390x systems when |
| // using -buildmode=c-archive or -buildmode=c-shared. The linker will |
| // arrange to invoke this function as a global constructor (for |
| // c-archive) or when the shared library is loaded (for c-shared). |
| // We expect argc and argv to be passed in the usual C ABI registers |
| // R2 and R3. |
| TEXT _rt0_s390x_lib(SB), NOSPLIT|NOFRAME, $0 |
| STMG R6, R15, 48(R15) |
| MOVD R2, _rt0_s390x_lib_argc<>(SB) |
| MOVD R3, _rt0_s390x_lib_argv<>(SB) |
| |
| // Save R6-R15 in the register save area of the calling function. |
| STMG R6, R15, 48(R15) |
| |
| // Allocate 80 bytes on the stack. |
| MOVD $-80(R15), R15 |
| |
| // Save F8-F15 in our stack frame. |
| FMOVD F8, 16(R15) |
| FMOVD F9, 24(R15) |
| FMOVD F10, 32(R15) |
| FMOVD F11, 40(R15) |
| FMOVD F12, 48(R15) |
| FMOVD F13, 56(R15) |
| FMOVD F14, 64(R15) |
| FMOVD F15, 72(R15) |
| |
| // Synchronous initialization. |
| MOVD $runtime·libpreinit(SB), R1 |
| BL R1 |
| |
| // Create a new thread to finish Go runtime initialization. |
| MOVD _cgo_sys_thread_create(SB), R1 |
| CMP R1, $0 |
| BEQ nocgo |
| MOVD $_rt0_s390x_lib_go(SB), R2 |
| MOVD $0, R3 |
| BL R1 |
| BR restore |
| |
| nocgo: |
| MOVD $0x800000, R1 // stacksize |
| MOVD R1, 0(R15) |
| MOVD $_rt0_s390x_lib_go(SB), R1 |
| MOVD R1, 8(R15) // fn |
| MOVD $runtime·newosproc(SB), R1 |
| BL R1 |
| |
| restore: |
| // Restore F8-F15 from our stack frame. |
| FMOVD 16(R15), F8 |
| FMOVD 24(R15), F9 |
| FMOVD 32(R15), F10 |
| FMOVD 40(R15), F11 |
| FMOVD 48(R15), F12 |
| FMOVD 56(R15), F13 |
| FMOVD 64(R15), F14 |
| FMOVD 72(R15), F15 |
| MOVD $80(R15), R15 |
| |
| // Restore R6-R15. |
| LMG 48(R15), R6, R15 |
| RET |
| |
| // _rt0_s390x_lib_go initializes the Go runtime. |
| // This is started in a separate thread by _rt0_s390x_lib. |
| TEXT _rt0_s390x_lib_go(SB), NOSPLIT|NOFRAME, $0 |
| MOVD _rt0_s390x_lib_argc<>(SB), R2 |
| MOVD _rt0_s390x_lib_argv<>(SB), R3 |
| MOVD $runtime·rt0_go(SB), R1 |
| BR R1 |
| |
| DATA _rt0_s390x_lib_argc<>(SB)/8, $0 |
| GLOBL _rt0_s390x_lib_argc<>(SB), NOPTR, $8 |
| DATA _rt0_s90x_lib_argv<>(SB)/8, $0 |
| GLOBL _rt0_s390x_lib_argv<>(SB), NOPTR, $8 |
| |
| TEXT runtime·rt0_go(SB),NOSPLIT|TOPFRAME,$0 |
| // R2 = argc; R3 = argv; R11 = temp; R13 = g; R15 = stack pointer |
| // C TLS base pointer in AR0:AR1 |
| |
| // initialize essential registers |
| XOR R0, R0 |
| |
| SUB $24, R15 |
| MOVW R2, 8(R15) // argc |
| MOVD R3, 16(R15) // argv |
| |
| // create istack out of the given (operating system) stack. |
| // _cgo_init may update stackguard. |
| MOVD $runtime·g0(SB), g |
| MOVD R15, R11 |
| SUB $(64*1024), R11 |
| MOVD R11, g_stackguard0(g) |
| MOVD R11, g_stackguard1(g) |
| MOVD R11, (g_stack+stack_lo)(g) |
| MOVD R15, (g_stack+stack_hi)(g) |
| |
| // if there is a _cgo_init, call it using the gcc ABI. |
| MOVD _cgo_init(SB), R11 |
| CMPBEQ R11, $0, nocgo |
| MOVW AR0, R4 // (AR0 << 32 | AR1) is the TLS base pointer; MOVD is translated to EAR |
| SLD $32, R4, R4 |
| MOVW AR1, R4 // arg 2: TLS base pointer |
| MOVD $setg_gcc<>(SB), R3 // arg 1: setg |
| MOVD g, R2 // arg 0: G |
| // C functions expect 160 bytes of space on caller stack frame |
| // and an 8-byte aligned stack pointer |
| MOVD R15, R9 // save current stack (R9 is preserved in the Linux ABI) |
| SUB $160, R15 // reserve 160 bytes |
| MOVD $~7, R6 |
| AND R6, R15 // 8-byte align |
| BL R11 // this call clobbers volatile registers according to Linux ABI (R0-R5, R14) |
| MOVD R9, R15 // restore stack |
| XOR R0, R0 // zero R0 |
| |
| nocgo: |
| // update stackguard after _cgo_init |
| MOVD (g_stack+stack_lo)(g), R2 |
| ADD $const__StackGuard, R2 |
| MOVD R2, g_stackguard0(g) |
| MOVD R2, g_stackguard1(g) |
| |
| // set the per-goroutine and per-mach "registers" |
| MOVD $runtime·m0(SB), R2 |
| |
| // save m->g0 = g0 |
| MOVD g, m_g0(R2) |
| // save m0 to g0->m |
| MOVD R2, g_m(g) |
| |
| BL runtime·check(SB) |
| |
| // argc/argv are already prepared on stack |
| BL runtime·args(SB) |
| BL runtime·osinit(SB) |
| BL runtime·schedinit(SB) |
| |
| // create a new goroutine to start program |
| MOVD $runtime·mainPC(SB), R2 // entry |
| SUB $16, R15 |
| MOVD R2, 8(R15) |
| MOVD $0, 0(R15) |
| BL runtime·newproc(SB) |
| ADD $16, R15 |
| |
| // start this M |
| BL runtime·mstart(SB) |
| |
| MOVD $0, 1(R0) |
| RET |
| |
| DATA runtime·mainPC+0(SB)/8,$runtime·main(SB) |
| GLOBL runtime·mainPC(SB),RODATA,$8 |
| |
| TEXT runtime·breakpoint(SB),NOSPLIT|NOFRAME,$0-0 |
| MOVD $0, 2(R0) |
| RET |
| |
| TEXT runtime·asminit(SB),NOSPLIT|NOFRAME,$0-0 |
| RET |
| |
| TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0 |
| CALL runtime·mstart0(SB) |
| RET // not reached |
| |
| /* |
| * go-routine |
| */ |
| |
| // void gogo(Gobuf*) |
| // restore state from Gobuf; longjmp |
| TEXT runtime·gogo(SB), NOSPLIT|NOFRAME, $0-8 |
| MOVD buf+0(FP), R5 |
| MOVD gobuf_g(R5), R6 |
| MOVD 0(R6), R7 // make sure g != nil |
| BR gogo<>(SB) |
| |
| TEXT gogo<>(SB), NOSPLIT|NOFRAME, $0 |
| MOVD R6, g |
| BL runtime·save_g(SB) |
| |
| MOVD 0(g), R4 |
| MOVD gobuf_sp(R5), R15 |
| MOVD gobuf_lr(R5), LR |
| MOVD gobuf_ret(R5), R3 |
| MOVD gobuf_ctxt(R5), R12 |
| MOVD $0, gobuf_sp(R5) |
| MOVD $0, gobuf_ret(R5) |
| MOVD $0, gobuf_lr(R5) |
| MOVD $0, gobuf_ctxt(R5) |
| CMP R0, R0 // set condition codes for == test, needed by stack split |
| MOVD gobuf_pc(R5), R6 |
| BR (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, $-8-8 |
| // Save caller state in g->sched |
| MOVD R15, (g_sched+gobuf_sp)(g) |
| MOVD LR, (g_sched+gobuf_pc)(g) |
| MOVD $0, (g_sched+gobuf_lr)(g) |
| |
| // Switch to m->g0 & its stack, call fn. |
| MOVD g, R3 |
| MOVD g_m(g), R8 |
| MOVD m_g0(R8), g |
| BL runtime·save_g(SB) |
| CMP g, R3 |
| BNE 2(PC) |
| BR runtime·badmcall(SB) |
| MOVD fn+0(FP), R12 // context |
| MOVD 0(R12), R4 // code pointer |
| MOVD (g_sched+gobuf_sp)(g), R15 // sp = m->g0->sched.sp |
| SUB $16, R15 |
| MOVD R3, 8(R15) |
| MOVD $0, 0(R15) |
| BL (R4) |
| BR 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 |
| BL (LR) // make sure this function is not leaf |
| RET |
| |
| // func systemstack(fn func()) |
| TEXT runtime·systemstack(SB), NOSPLIT, $0-8 |
| MOVD fn+0(FP), R3 // R3 = fn |
| MOVD R3, R12 // context |
| MOVD g_m(g), R4 // R4 = m |
| |
| MOVD m_gsignal(R4), R5 // R5 = gsignal |
| CMPBEQ g, R5, noswitch |
| |
| MOVD m_g0(R4), R5 // R5 = g0 |
| CMPBEQ g, R5, noswitch |
| |
| MOVD m_curg(R4), R6 |
| CMPBEQ g, R6, switch |
| |
| // Bad: g is not gsignal, not g0, not curg. What is it? |
| // Hide call from linker nosplit analysis. |
| MOVD $runtime·badsystemstack(SB), R3 |
| BL (R3) |
| BL runtime·abort(SB) |
| |
| switch: |
| // save our state in g->sched. Pretend to |
| // be systemstack_switch if the G stack is scanned. |
| BL gosave_systemstack_switch<>(SB) |
| |
| // switch to g0 |
| MOVD R5, g |
| BL runtime·save_g(SB) |
| MOVD (g_sched+gobuf_sp)(g), R15 |
| |
| // call target function |
| MOVD 0(R12), R3 // code pointer |
| BL (R3) |
| |
| // switch back to g |
| MOVD g_m(g), R3 |
| MOVD m_curg(R3), g |
| BL runtime·save_g(SB) |
| MOVD (g_sched+gobuf_sp)(g), R15 |
| MOVD $0, (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. |
| MOVD 0(R12), R3 // code pointer |
| MOVD 0(R15), LR // restore LR |
| ADD $8, R15 |
| BR (R3) |
| |
| /* |
| * support for morestack |
| */ |
| |
| // Called during function prolog when more stack is needed. |
| // Caller has already loaded: |
| // R3: framesize, R4: argsize, 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). |
| MOVD g_m(g), R7 |
| MOVD m_g0(R7), R8 |
| CMPBNE g, R8, 3(PC) |
| BL runtime·badmorestackg0(SB) |
| BL runtime·abort(SB) |
| |
| // Cannot grow signal stack (m->gsignal). |
| MOVD m_gsignal(R7), R8 |
| CMP g, R8 |
| BNE 3(PC) |
| BL runtime·badmorestackgsignal(SB) |
| BL runtime·abort(SB) |
| |
| // Called from f. |
| // Set g->sched to context in f. |
| MOVD R15, (g_sched+gobuf_sp)(g) |
| MOVD LR, R8 |
| MOVD R8, (g_sched+gobuf_pc)(g) |
| MOVD R5, (g_sched+gobuf_lr)(g) |
| MOVD R12, (g_sched+gobuf_ctxt)(g) |
| |
| // Called from f. |
| // Set m->morebuf to f's caller. |
| MOVD R5, (m_morebuf+gobuf_pc)(R7) // f's caller's PC |
| MOVD R15, (m_morebuf+gobuf_sp)(R7) // f's caller's SP |
| MOVD g, (m_morebuf+gobuf_g)(R7) |
| |
| // Call newstack on m->g0's stack. |
| MOVD m_g0(R7), g |
| BL runtime·save_g(SB) |
| MOVD (g_sched+gobuf_sp)(g), R15 |
| // Create a stack frame on g0 to call newstack. |
| MOVD $0, -8(R15) // Zero saved LR in frame |
| SUB $8, R15 |
| BL 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 |
| MOVD $0, R12 |
| BR runtime·morestack(SB) |
| |
| // 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) \ |
| MOVD $MAXSIZE, R4; \ |
| CMP R3, R4; \ |
| BGT 3(PC); \ |
| MOVD $NAME(SB), R5; \ |
| BR (R5) |
| // Note: can't just "BR NAME(SB)" - bad inlining results. |
| |
| TEXT ·reflectcall(SB), NOSPLIT, $-8-48 |
| MOVWZ frameSize+32(FP), R3 |
| 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) |
| MOVD $runtime·badreflectcall(SB), R5 |
| BR (R5) |
| |
| #define CALLFN(NAME,MAXSIZE) \ |
| TEXT NAME(SB), WRAPPER, $MAXSIZE-48; \ |
| NO_LOCAL_POINTERS; \ |
| /* copy arguments to stack */ \ |
| MOVD stackArgs+16(FP), R4; \ |
| MOVWZ stackArgsSize+24(FP), R5; \ |
| MOVD $stack-MAXSIZE(SP), R6; \ |
| loopArgs: /* copy 256 bytes at a time */ \ |
| CMP R5, $256; \ |
| BLT tailArgs; \ |
| SUB $256, R5; \ |
| MVC $256, 0(R4), 0(R6); \ |
| MOVD $256(R4), R4; \ |
| MOVD $256(R6), R6; \ |
| BR loopArgs; \ |
| tailArgs: /* copy remaining bytes */ \ |
| CMP R5, $0; \ |
| BEQ callFunction; \ |
| SUB $1, R5; \ |
| EXRL $callfnMVC<>(SB), R5; \ |
| callFunction: \ |
| MOVD f+8(FP), R12; \ |
| MOVD (R12), R8; \ |
| PCDATA $PCDATA_StackMapIndex, $0; \ |
| BL (R8); \ |
| /* copy return values back */ \ |
| MOVD stackArgsType+0(FP), R7; \ |
| MOVD stackArgs+16(FP), R6; \ |
| MOVWZ stackArgsSize+24(FP), R5; \ |
| MOVD $stack-MAXSIZE(SP), R4; \ |
| MOVWZ stackRetOffset+28(FP), R1; \ |
| ADD R1, R4; \ |
| ADD R1, R6; \ |
| SUB R1, R5; \ |
| BL 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 |
| MOVD R7, 8(R15) |
| MOVD R6, 16(R15) |
| MOVD R4, 24(R15) |
| MOVD R5, 32(R15) |
| MOVD $0, 40(R15) |
| BL 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) |
| |
| // Not a function: target for EXRL (execute relative long) instruction. |
| TEXT callfnMVC<>(SB),NOSPLIT|NOFRAME,$0-0 |
| MVC $1, 0(R4), 0(R6) |
| |
| 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 R1. |
| TEXT gosave_systemstack_switch<>(SB),NOSPLIT|NOFRAME,$0 |
| MOVD $runtime·systemstack_switch(SB), R1 |
| ADD $16, R1 // get past prologue |
| MOVD R1, (g_sched+gobuf_pc)(g) |
| MOVD R15, (g_sched+gobuf_sp)(g) |
| MOVD $0, (g_sched+gobuf_lr)(g) |
| MOVD $0, (g_sched+gobuf_ret)(g) |
| // Assert ctxt is zero. See func save. |
| MOVD (g_sched+gobuf_ctxt)(g), R1 |
| CMPBEQ R1, $0, 2(PC) |
| BL 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 |
| // R2 = argc; R3 = argv; R11 = temp; R13 = g; R15 = stack pointer |
| // C TLS base pointer in AR0:AR1 |
| MOVD fn+0(FP), R3 |
| MOVD arg+8(FP), R4 |
| |
| MOVD R15, R2 // save original stack pointer |
| MOVD g, R5 |
| |
| // 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. |
| MOVD g_m(g), R6 |
| MOVD m_gsignal(R6), R7 |
| CMPBEQ R7, g, g0 |
| MOVD m_g0(R6), R7 |
| CMPBEQ R7, g, g0 |
| BL gosave_systemstack_switch<>(SB) |
| MOVD R7, g |
| BL runtime·save_g(SB) |
| MOVD (g_sched+gobuf_sp)(g), R15 |
| |
| // Now on a scheduling stack (a pthread-created stack). |
| g0: |
| // Save room for two of our pointers, plus 160 bytes of callee |
| // save area that lives on the caller stack. |
| SUB $176, R15 |
| MOVD $~7, R6 |
| AND R6, R15 // 8-byte alignment for gcc ABI |
| MOVD R5, 168(R15) // save old g on stack |
| MOVD (g_stack+stack_hi)(R5), R5 |
| SUB R2, R5 |
| MOVD R5, 160(R15) // save depth in old g stack (can't just save SP, as stack might be copied during a callback) |
| MOVD $0, 0(R15) // clear back chain pointer (TODO can we give it real back trace information?) |
| MOVD R4, R2 // arg in R2 |
| BL R3 // can clobber: R0-R5, R14, F0-F3, F5, F7-F15 |
| |
| XOR R0, R0 // set R0 back to 0. |
| // Restore g, stack pointer. |
| MOVD 168(R15), g |
| BL runtime·save_g(SB) |
| MOVD (g_stack+stack_hi)(g), R5 |
| MOVD 160(R15), R6 |
| SUB R6, R5 |
| MOVD R5, R15 |
| |
| MOVW R2, ret+16(FP) |
| RET |
| |
| // 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), R3 |
| CMPBEQ R3, $0, nocgo |
| BL 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. |
| CMPBEQ g, $0, needm |
| |
| MOVD g_m(g), R8 |
| MOVD R8, savedm-8(SP) |
| BR havem |
| |
| needm: |
| MOVD g, savedm-8(SP) // g is zero, so is m. |
| MOVD $runtime·needm(SB), R3 |
| BL (R3) |
| |
| // 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. |
| MOVD g_m(g), R8 |
| MOVD m_g0(R8), R3 |
| MOVD R15, (g_sched+gobuf_sp)(R3) |
| |
| 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(R1) aka savedsp-16(SP). |
| MOVD m_g0(R8), R3 |
| MOVD (g_sched+gobuf_sp)(R3), R4 |
| MOVD R4, savedsp-24(SP) // must match frame size |
| MOVD R15, (g_sched+gobuf_sp)(R3) |
| |
| // 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. |
| MOVD m_curg(R8), g |
| BL runtime·save_g(SB) |
| MOVD (g_sched+gobuf_sp)(g), R4 // prepare stack as R4 |
| MOVD (g_sched+gobuf_pc)(g), R5 |
| MOVD R5, -(24+8)(R4) // "saved LR"; must match frame size |
| // Gather our arguments into registers. |
| MOVD fn+0(FP), R1 |
| MOVD frame+8(FP), R2 |
| MOVD ctxt+16(FP), R3 |
| MOVD $-(24+8)(R4), R15 // switch stack; must match frame size |
| MOVD R1, 8(R15) |
| MOVD R2, 16(R15) |
| MOVD R3, 24(R15) |
| BL runtime·cgocallbackg(SB) |
| |
| // Restore g->sched (== m->curg->sched) from saved values. |
| MOVD 0(R15), R5 |
| MOVD R5, (g_sched+gobuf_pc)(g) |
| MOVD $(24+8)(R15), R4 // must match frame size |
| MOVD R4, (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.) |
| MOVD g_m(g), R8 |
| MOVD m_g0(R8), g |
| BL runtime·save_g(SB) |
| MOVD (g_sched+gobuf_sp)(g), R15 |
| MOVD savedsp-24(SP), R4 // must match frame size |
| MOVD R4, (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. |
| MOVD savedm-8(SP), R6 |
| CMPBNE R6, $0, droppedm |
| MOVD $runtime·dropm(SB), R3 |
| BL (R3) |
| droppedm: |
| |
| // Done! |
| RET |
| |
| // void setg(G*); set g. for use by needm. |
| TEXT runtime·setg(SB), NOSPLIT, $0-8 |
| MOVD gg+0(FP), g |
| // This only happens if iscgo, so jump straight to save_g |
| BL runtime·save_g(SB) |
| RET |
| |
| // void setg_gcc(G*); set g in C TLS. |
| // Must obey the gcc calling convention. |
| TEXT setg_gcc<>(SB),NOSPLIT|NOFRAME,$0-0 |
| // The standard prologue clobbers LR (R14), which is callee-save in |
| // the C ABI, so we have to use NOFRAME and save LR ourselves. |
| MOVD LR, R1 |
| // Also save g, R10, and R11 since they're callee-save in C ABI |
| MOVD R10, R3 |
| MOVD g, R4 |
| MOVD R11, R5 |
| |
| MOVD R2, g |
| BL runtime·save_g(SB) |
| |
| MOVD R5, R11 |
| MOVD R4, g |
| MOVD R3, R10 |
| MOVD R1, LR |
| RET |
| |
| TEXT runtime·abort(SB),NOSPLIT|NOFRAME,$0-0 |
| MOVW (R0), R0 |
| UNDEF |
| |
| // int64 runtime·cputicks(void) |
| TEXT runtime·cputicks(SB),NOSPLIT,$0-8 |
| // The TOD clock on s390 counts from the year 1900 in ~250ps intervals. |
| // This means that since about 1972 the msb has been set, making the |
| // result of a call to STORE CLOCK (stck) a negative number. |
| // We clear the msb to make it positive. |
| STCK ret+0(FP) // serialises before and after call |
| MOVD ret+0(FP), R3 // R3 will wrap to 0 in the year 2043 |
| SLD $1, R3 |
| SRD $1, R3 |
| MOVD R3, ret+0(FP) |
| RET |
| |
| // AES hashing not implemented for s390x |
| 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, R3 |
| RET |
| |
| // Called from cgo wrappers, this function returns g->m->curg.stack.hi. |
| // Must obey the gcc calling convention. |
| TEXT _cgo_topofstack(SB),NOSPLIT|NOFRAME,$0 |
| // g (R13), R10, R11 and LR (R14) are callee-save in the C ABI, so save them |
| MOVD g, R1 |
| MOVD R10, R3 |
| MOVD LR, R4 |
| MOVD R11, R5 |
| |
| BL runtime·load_g(SB) // clobbers g (R13), R10, R11 |
| MOVD g_m(g), R2 |
| MOVD m_curg(R2), R2 |
| MOVD (g_stack+stack_hi)(R2), R2 |
| |
| MOVD R1, g |
| MOVD R3, R10 |
| MOVD R4, LR |
| MOVD R5, R11 |
| RET |
| |
| // The top-most function running on a goroutine |
| // returns to goexit+PCQuantum. |
| TEXT runtime·goexit(SB),NOSPLIT|NOFRAME|TOPFRAME,$0-0 |
| BYTE $0x07; BYTE $0x00; // 2-byte nop |
| BL runtime·goexit1(SB) // does not return |
| // traceback from goexit1 must hit code range of goexit |
| BYTE $0x07; BYTE $0x00; // 2-byte nop |
| |
| TEXT ·publicationBarrier(SB),NOSPLIT|NOFRAME,$0-0 |
| // Stores are already ordered on s390x, so this is just a |
| // compile barrier. |
| RET |
| |
| // This is called from .init_array and follows the platform, not Go, ABI. |
| // We are overly conservative. We could only save the registers we use. |
| // However, since this function is only called once per loaded module |
| // performance is unimportant. |
| TEXT runtime·addmoduledata(SB),NOSPLIT|NOFRAME,$0-0 |
| // Save R6-R15 in the register save area of the calling function. |
| // Don't bother saving F8-F15 as we aren't doing any calls. |
| STMG R6, R15, 48(R15) |
| |
| // append the argument (passed in R2, as per the ELF ABI) to the |
| // moduledata linked list. |
| MOVD runtime·lastmoduledatap(SB), R1 |
| MOVD R2, moduledata_next(R1) |
| MOVD R2, runtime·lastmoduledatap(SB) |
| |
| // Restore R6-R15. |
| LMG 48(R15), R6, R15 |
| RET |
| |
| TEXT ·checkASM(SB),NOSPLIT,$0-1 |
| MOVB $1, 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: |
| // - R2 is the destination of the write |
| // - R3 is the value being written at R2. |
| // It clobbers R10 (the temp register). |
| // It does not clobber any other general-purpose registers, |
| // but may clobber others (e.g., floating point registers). |
| TEXT runtime·gcWriteBarrier(SB),NOSPLIT,$104 |
| // Save the registers clobbered by the fast path. |
| MOVD R1, 96(R15) |
| MOVD R4, 104(R15) |
| MOVD g_m(g), R1 |
| MOVD m_p(R1), R1 |
| // Increment wbBuf.next position. |
| MOVD $16, R4 |
| ADD (p_wbBuf+wbBuf_next)(R1), R4 |
| MOVD R4, (p_wbBuf+wbBuf_next)(R1) |
| MOVD (p_wbBuf+wbBuf_end)(R1), R1 |
| // Record the write. |
| MOVD R3, -16(R4) // Record value |
| MOVD (R2), R10 // TODO: This turns bad writes into bad reads. |
| MOVD R10, -8(R4) // Record *slot |
| // Is the buffer full? |
| CMPBEQ R4, R1, flush |
| ret: |
| MOVD 96(R15), R1 |
| MOVD 104(R15), R4 |
| // Do the write. |
| MOVD R3, (R2) |
| RET |
| |
| flush: |
| // Save all general purpose registers since these could be |
| // clobbered by wbBufFlush and were not saved by the caller. |
| STMG R2, R3, 8(R15) // set R2 and R3 as arguments for wbBufFlush |
| MOVD R0, 24(R15) |
| // R1 already saved. |
| // R4 already saved. |
| STMG R5, R12, 32(R15) // save R5 - R12 |
| // R13 is g. |
| // R14 is LR. |
| // R15 is SP. |
| |
| // This takes arguments R2 and R3. |
| CALL runtime·wbBufFlush(SB) |
| |
| LMG 8(R15), R2, R3 // restore R2 - R3 |
| MOVD 24(R15), R0 // restore R0 |
| LMG 32(R15), R5, R12 // restore R5 - R12 |
| 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 |
| MOVD R0, x+0(FP) |
| MOVD R1, y+8(FP) |
| JMP runtime·goPanicIndex(SB) |
| TEXT runtime·panicIndexU(SB),NOSPLIT,$0-16 |
| MOVD R0, x+0(FP) |
| MOVD R1, y+8(FP) |
| JMP runtime·goPanicIndexU(SB) |
| TEXT runtime·panicSliceAlen(SB),NOSPLIT,$0-16 |
| MOVD R1, x+0(FP) |
| MOVD R2, y+8(FP) |
| JMP runtime·goPanicSliceAlen(SB) |
| TEXT runtime·panicSliceAlenU(SB),NOSPLIT,$0-16 |
| MOVD R1, x+0(FP) |
| MOVD R2, y+8(FP) |
| JMP runtime·goPanicSliceAlenU(SB) |
| TEXT runtime·panicSliceAcap(SB),NOSPLIT,$0-16 |
| MOVD R1, x+0(FP) |
| MOVD R2, y+8(FP) |
| JMP runtime·goPanicSliceAcap(SB) |
| TEXT runtime·panicSliceAcapU(SB),NOSPLIT,$0-16 |
| MOVD R1, x+0(FP) |
| MOVD R2, y+8(FP) |
| JMP runtime·goPanicSliceAcapU(SB) |
| TEXT runtime·panicSliceB(SB),NOSPLIT,$0-16 |
| MOVD R0, x+0(FP) |
| MOVD R1, y+8(FP) |
| JMP runtime·goPanicSliceB(SB) |
| TEXT runtime·panicSliceBU(SB),NOSPLIT,$0-16 |
| MOVD R0, x+0(FP) |
| MOVD R1, y+8(FP) |
| JMP runtime·goPanicSliceBU(SB) |
| TEXT runtime·panicSlice3Alen(SB),NOSPLIT,$0-16 |
| MOVD R2, x+0(FP) |
| MOVD R3, y+8(FP) |
| JMP runtime·goPanicSlice3Alen(SB) |
| TEXT runtime·panicSlice3AlenU(SB),NOSPLIT,$0-16 |
| MOVD R2, x+0(FP) |
| MOVD R3, y+8(FP) |
| JMP runtime·goPanicSlice3AlenU(SB) |
| TEXT runtime·panicSlice3Acap(SB),NOSPLIT,$0-16 |
| MOVD R2, x+0(FP) |
| MOVD R3, y+8(FP) |
| JMP runtime·goPanicSlice3Acap(SB) |
| TEXT runtime·panicSlice3AcapU(SB),NOSPLIT,$0-16 |
| MOVD R2, x+0(FP) |
| MOVD R3, y+8(FP) |
| JMP runtime·goPanicSlice3AcapU(SB) |
| TEXT runtime·panicSlice3B(SB),NOSPLIT,$0-16 |
| MOVD R1, x+0(FP) |
| MOVD R2, y+8(FP) |
| JMP runtime·goPanicSlice3B(SB) |
| TEXT runtime·panicSlice3BU(SB),NOSPLIT,$0-16 |
| MOVD R1, x+0(FP) |
| MOVD R2, y+8(FP) |
| JMP runtime·goPanicSlice3BU(SB) |
| TEXT runtime·panicSlice3C(SB),NOSPLIT,$0-16 |
| MOVD R0, x+0(FP) |
| MOVD R1, y+8(FP) |
| JMP runtime·goPanicSlice3C(SB) |
| TEXT runtime·panicSlice3CU(SB),NOSPLIT,$0-16 |
| MOVD R0, x+0(FP) |
| MOVD R1, y+8(FP) |
| JMP runtime·goPanicSlice3CU(SB) |
| TEXT runtime·panicSliceConvert(SB),NOSPLIT,$0-16 |
| MOVD R2, x+0(FP) |
| MOVD R3, y+8(FP) |
| JMP runtime·goPanicSliceConvert(SB) |
