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Diffstat (limited to 'src/runtime/asm_ppc64x.s')
| -rw-r--r-- | src/runtime/asm_ppc64x.s | 1038 |
1 files changed, 1038 insertions, 0 deletions
diff --git a/src/runtime/asm_ppc64x.s b/src/runtime/asm_ppc64x.s new file mode 100644 index 0000000..dc34c0e --- /dev/null +++ b/src/runtime/asm_ppc64x.s @@ -0,0 +1,1038 @@ +// Copyright 2014 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. + +// +build ppc64 ppc64le + +#include "go_asm.h" +#include "go_tls.h" +#include "funcdata.h" +#include "textflag.h" +#include "asm_ppc64x.h" + +#ifdef GOOS_aix +#define cgoCalleeStackSize 48 +#else +#define cgoCalleeStackSize 32 +#endif + +TEXT runtime·rt0_go(SB),NOSPLIT,$0 + // R1 = stack; R3 = argc; R4 = argv; R13 = C TLS base pointer + + // initialize essential registers + BL runtime·reginit(SB) + + SUB $(FIXED_FRAME+16), R1 + MOVD R2, 24(R1) // stash the TOC pointer away again now we've created a new frame + MOVW R3, FIXED_FRAME+0(R1) // argc + MOVD R4, FIXED_FRAME+8(R1) // argv + + // create istack out of the given (operating system) stack. + // _cgo_init may update stackguard. + MOVD $runtime·g0(SB), g + BL runtime·save_g(SB) + MOVD $(-64*1024), R31 + ADD R31, R1, R3 + MOVD R3, g_stackguard0(g) + MOVD R3, g_stackguard1(g) + MOVD R3, (g_stack+stack_lo)(g) + MOVD R1, (g_stack+stack_hi)(g) + + // if there is a _cgo_init, call it using the gcc ABI. + MOVD _cgo_init(SB), R12 + CMP R0, R12 + BEQ nocgo +#ifdef GOARCH_ppc64 + // ppc64 use elf ABI v1. we must get the real entry address from + // first slot of the function descriptor before call. + MOVD 8(R12), R2 + MOVD (R12), R12 +#endif + MOVD R12, CTR // r12 = "global function entry point" + MOVD R13, R5 // arg 2: TLS base pointer + MOVD $setg_gcc<>(SB), R4 // arg 1: setg + MOVD g, R3 // arg 0: G + // C functions expect 32 (48 for AIX) bytes of space on caller + // stack frame and a 16-byte aligned R1 + MOVD R1, R14 // save current stack + SUB $cgoCalleeStackSize, R1 // reserve the callee area + RLDCR $0, R1, $~15, R1 // 16-byte align + BL (CTR) // may clobber R0, R3-R12 + MOVD R14, R1 // restore stack +#ifndef GOOS_aix + MOVD 24(R1), R2 +#endif + XOR R0, R0 // fix R0 + +nocgo: + // update stackguard after _cgo_init + MOVD (g_stack+stack_lo)(g), R3 + ADD $const__StackGuard, R3 + MOVD R3, g_stackguard0(g) + MOVD R3, g_stackguard1(g) + + // set the per-goroutine and per-mach "registers" + MOVD $runtime·m0(SB), R3 + + // save m->g0 = g0 + MOVD g, m_g0(R3) + // save m0 to g0->m + MOVD R3, g_m(g) + + BL runtime·check(SB) + + // args are already prepared + BL runtime·args(SB) + BL runtime·osinit(SB) + BL runtime·schedinit(SB) + + // create a new goroutine to start program + MOVD $runtime·mainPC(SB), R3 // entry + MOVDU R3, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + BL runtime·newproc(SB) + ADD $(16+FIXED_FRAME), R1 + + // start this M + BL runtime·mstart(SB) + + MOVD R0, 0(R0) + RET + +DATA runtime·mainPC+0(SB)/8,$runtime·main(SB) +GLOBL runtime·mainPC(SB),RODATA,$8 + +TEXT runtime·breakpoint(SB),NOSPLIT|NOFRAME,$0-0 + MOVD R0, 0(R0) // TODO: TD + RET + +TEXT runtime·asminit(SB),NOSPLIT|NOFRAME,$0-0 + RET + +// Any changes must be reflected to runtime/cgo/gcc_aix_ppc64.S:.crosscall_ppc64 +TEXT _cgo_reginit(SB),NOSPLIT|NOFRAME,$0-0 + // crosscall_ppc64 and crosscall2 need to reginit, but can't + // get at the 'runtime.reginit' symbol. + BR runtime·reginit(SB) + +TEXT runtime·reginit(SB),NOSPLIT|NOFRAME,$0-0 + // set R0 to zero, it's expected by the toolchain + XOR R0, R0 + RET + +/* + * go-routine + */ + +// void gosave(Gobuf*) +// save state in Gobuf; setjmp +TEXT runtime·gosave(SB), NOSPLIT|NOFRAME, $0-8 + MOVD buf+0(FP), R3 + MOVD R1, gobuf_sp(R3) + MOVD LR, R31 + MOVD R31, gobuf_pc(R3) + MOVD g, gobuf_g(R3) + MOVD R0, gobuf_lr(R3) + MOVD R0, gobuf_ret(R3) + // Assert ctxt is zero. See func save. + MOVD gobuf_ctxt(R3), R3 + CMP R0, R3 + BEQ 2(PC) + BL runtime·badctxt(SB) + RET + +// void gogo(Gobuf*) +// restore state from Gobuf; longjmp +TEXT runtime·gogo(SB), NOSPLIT, $16-8 + MOVD buf+0(FP), R5 + MOVD gobuf_g(R5), g // make sure g is not nil + BL runtime·save_g(SB) + + MOVD 0(g), R4 + MOVD gobuf_sp(R5), R1 + MOVD gobuf_lr(R5), R31 +#ifndef GOOS_aix + MOVD 24(R1), R2 // restore R2 +#endif + MOVD R31, LR + MOVD gobuf_ret(R5), R3 + MOVD gobuf_ctxt(R5), R11 + MOVD R0, gobuf_sp(R5) + MOVD R0, gobuf_ret(R5) + MOVD R0, gobuf_lr(R5) + MOVD R0, gobuf_ctxt(R5) + CMP R0, R0 // set condition codes for == test, needed by stack split + MOVD gobuf_pc(R5), R12 + MOVD R12, CTR + BR (CTR) + +// 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|NOFRAME, $0-8 + // Save caller state in g->sched + MOVD R1, (g_sched+gobuf_sp)(g) + MOVD LR, R31 + MOVD R31, (g_sched+gobuf_pc)(g) + MOVD R0, (g_sched+gobuf_lr)(g) + MOVD g, (g_sched+gobuf_g)(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), R11 // context + MOVD 0(R11), R12 // code pointer + MOVD R12, CTR + MOVD (g_sched+gobuf_sp)(g), R1 // sp = m->g0->sched.sp + MOVDU R3, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + MOVDU R0, -8(R1) + BL (CTR) + MOVD 24(R1), R2 + 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 + // We have several undefs here so that 16 bytes past + // $runtime·systemstack_switch lies within them whether or not the + // instructions that derive r2 from r12 are there. + UNDEF + UNDEF + 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, R11 // context + MOVD g_m(g), R4 // R4 = m + + MOVD m_gsignal(R4), R5 // R5 = gsignal + CMP g, R5 + BEQ noswitch + + MOVD m_g0(R4), R5 // R5 = g0 + CMP g, R5 + BEQ noswitch + + MOVD m_curg(R4), R6 + CMP g, R6 + BEQ switch + + // Bad: g is not gsignal, not g0, not curg. What is it? + // Hide call from linker nosplit analysis. + MOVD $runtime·badsystemstack(SB), R12 + MOVD R12, CTR + BL (CTR) + BL runtime·abort(SB) + +switch: + // save our state in g->sched. Pretend to + // be systemstack_switch if the G stack is scanned. + MOVD $runtime·systemstack_switch(SB), R6 + ADD $16, R6 // get past prologue (including r2-setting instructions when they're there) + MOVD R6, (g_sched+gobuf_pc)(g) + MOVD R1, (g_sched+gobuf_sp)(g) + MOVD R0, (g_sched+gobuf_lr)(g) + MOVD g, (g_sched+gobuf_g)(g) + + // switch to g0 + MOVD R5, g + BL runtime·save_g(SB) + MOVD (g_sched+gobuf_sp)(g), R3 + // make it look like mstart called systemstack on g0, to stop traceback + SUB $FIXED_FRAME, R3 + MOVD $runtime·mstart(SB), R4 + MOVD R4, 0(R3) + MOVD R3, R1 + + // call target function + MOVD 0(R11), R12 // code pointer + MOVD R12, CTR + BL (CTR) + + // restore TOC pointer. It seems unlikely that we will use systemstack + // to call a function defined in another module, but the results of + // doing so would be so confusing that it's worth doing this. + MOVD g_m(g), R3 + MOVD m_curg(R3), g + MOVD (g_sched+gobuf_sp)(g), R3 +#ifndef GOOS_aix + MOVD 24(R3), R2 +#endif + // 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), R1 + MOVD R0, (g_sched+gobuf_sp)(g) + RET + +noswitch: + // already on m stack, just call directly + // On other arches we do a tail call here, but it appears to be + // impossible to tail call a function pointer in shared mode on + // ppc64 because the caller is responsible for restoring the TOC. + MOVD 0(R11), R12 // code pointer + MOVD R12, CTR + BL (CTR) +#ifndef GOOS_aix + MOVD 24(R1), R2 +#endif + RET + +/* + * 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 + CMP g, R8 + BNE 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 R1, (g_sched+gobuf_sp)(g) + MOVD LR, R8 + MOVD R8, (g_sched+gobuf_pc)(g) + MOVD R5, (g_sched+gobuf_lr)(g) + MOVD R11, (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 R1, (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), R1 + MOVDU R0, -(FIXED_FRAME+0)(R1) // create a call frame on g0 + 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 R0, R11 + BR runtime·morestack(SB) + +// 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) \ + MOVD $MAXSIZE, R31; \ + CMP R3, R31; \ + BGT 4(PC); \ + MOVD $NAME(SB), R12; \ + MOVD R12, CTR; \ + BR (CTR) +// Note: can't just "BR NAME(SB)" - bad inlining results. + +TEXT ·reflectcall(SB), NOSPLIT|NOFRAME, $0-32 + MOVWZ argsize+24(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), R12 + MOVD R12, CTR + BR (CTR) + +#define CALLFN(NAME,MAXSIZE) \ +TEXT NAME(SB), WRAPPER, $MAXSIZE-24; \ + NO_LOCAL_POINTERS; \ + /* copy arguments to stack */ \ + MOVD arg+16(FP), R3; \ + MOVWZ argsize+24(FP), R4; \ + MOVD R1, R5; \ + CMP R4, $8; \ + BLT tailsetup; \ + /* copy 8 at a time if possible */ \ + ADD $(FIXED_FRAME-8), R5; \ + SUB $8, R3; \ +top: \ + MOVDU 8(R3), R7; \ + MOVDU R7, 8(R5); \ + SUB $8, R4; \ + CMP R4, $8; \ + BGE top; \ + /* handle remaining bytes */ \ + CMP $0, R4; \ + BEQ callfn; \ + ADD $7, R3; \ + ADD $7, R5; \ + BR tail; \ +tailsetup: \ + CMP $0, R4; \ + BEQ callfn; \ + ADD $(FIXED_FRAME-1), R5; \ + SUB $1, R3; \ +tail: \ + MOVBU 1(R3), R6; \ + MOVBU R6, 1(R5); \ + SUB $1, R4; \ + CMP $0, R4; \ + BGT tail; \ +callfn: \ + /* call function */ \ + MOVD f+8(FP), R11; \ +#ifdef GOOS_aix \ + /* AIX won't trigger a SIGSEGV if R11 = nil */ \ + /* So it manually triggers it */ \ + CMP R0, R11 \ + BNE 2(PC) \ + MOVD R0, 0(R0) \ +#endif \ + MOVD (R11), R12; \ + MOVD R12, CTR; \ + PCDATA $PCDATA_StackMapIndex, $0; \ + BL (CTR); \ +#ifndef GOOS_aix \ + MOVD 24(R1), R2; \ +#endif \ + /* copy return values back */ \ + MOVD argtype+0(FP), R7; \ + MOVD arg+16(FP), R3; \ + MOVWZ n+24(FP), R4; \ + MOVWZ retoffset+28(FP), R6; \ + ADD $FIXED_FRAME, R1, R5; \ + ADD R6, R5; \ + ADD R6, R3; \ + SUB R6, R4; \ + 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, $32-0 + MOVD R7, FIXED_FRAME+0(R1) + MOVD R3, FIXED_FRAME+8(R1) + MOVD R5, FIXED_FRAME+16(R1) + MOVD R4, FIXED_FRAME+24(R1) + 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) + +TEXT runtime·procyield(SB),NOSPLIT|NOFRAME,$0-4 + MOVW cycles+0(FP), R7 + // POWER does not have a pause/yield instruction equivalent. + // Instead, we can lower the program priority by setting the + // Program Priority Register prior to the wait loop and set it + // back to default afterwards. On Linux, the default priority is + // medium-low. For details, see page 837 of the ISA 3.0. + OR R1, R1, R1 // Set PPR priority to low +again: + SUB $1, R7 + CMP $0, R7 + BNE again + OR R6, R6, R6 // Set PPR priority back to medium-low + RET + +// void jmpdefer(fv, sp); +// called from deferreturn. +// 1. grab stored LR for caller +// 2. sub 8 bytes to get back to either nop or toc reload before deferreturn +// 3. BR to fn +// When dynamically linking Go, it is not sufficient to rewind to the BL +// deferreturn -- we might be jumping between modules and so we need to reset +// the TOC pointer in r2. To do this, codegen inserts MOVD 24(R1), R2 *before* +// the BL deferreturn and jmpdefer rewinds to that. +TEXT runtime·jmpdefer(SB), NOSPLIT|NOFRAME, $0-16 + MOVD 0(R1), R31 + SUB $8, R31 + MOVD R31, LR + + MOVD fv+0(FP), R11 + MOVD argp+8(FP), R1 + SUB $FIXED_FRAME, R1 +#ifdef GOOS_aix + // AIX won't trigger a SIGSEGV if R11 = nil + // So it manually triggers it + CMP R0, R11 + BNE 2(PC) + MOVD R0, 0(R0) +#endif + MOVD 0(R11), R12 + MOVD R12, CTR + BR (CTR) + +// Save state of caller into g->sched. Smashes R31. +TEXT gosave<>(SB),NOSPLIT|NOFRAME,$0 + MOVD LR, R31 + MOVD R31, (g_sched+gobuf_pc)(g) + MOVD R1, (g_sched+gobuf_sp)(g) + MOVD R0, (g_sched+gobuf_lr)(g) + MOVD R0, (g_sched+gobuf_ret)(g) + // Assert ctxt is zero. See func save. + MOVD (g_sched+gobuf_ctxt)(g), R31 + CMP R0, R31 + BEQ 2(PC) + BL runtime·badctxt(SB) + RET + +#ifdef GOOS_aix +#define asmcgocallSaveOffset cgoCalleeStackSize + 8 +#else +#define asmcgocallSaveOffset cgoCalleeStackSize +#endif + +// 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 + MOVD fn+0(FP), R3 + MOVD arg+8(FP), R4 + + MOVD R1, R7 // 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. + // Moreover, if it's called inside the signal handler, it must not switch + // to g0 as it can be in use by another syscall. + MOVD g_m(g), R8 + MOVD m_gsignal(R8), R6 + CMP R6, g + BEQ g0 + MOVD m_g0(R8), R6 + CMP R6, g + BEQ g0 + BL gosave<>(SB) + MOVD R6, g + BL runtime·save_g(SB) + MOVD (g_sched+gobuf_sp)(g), R1 + + // Now on a scheduling stack (a pthread-created stack). +g0: +#ifdef GOOS_aix + // Create a fake LR to improve backtrace. + MOVD $runtime·asmcgocall(SB), R6 + MOVD R6, 16(R1) + // AIX also save one argument on the stack. + SUB $8, R1 +#endif + // Save room for two of our pointers, plus the callee + // save area that lives on the caller stack. + SUB $(asmcgocallSaveOffset+16), R1 + RLDCR $0, R1, $~15, R1 // 16-byte alignment for gcc ABI + MOVD R5, (asmcgocallSaveOffset+8)(R1)// save old g on stack + MOVD (g_stack+stack_hi)(R5), R5 + SUB R7, R5 + MOVD R5, asmcgocallSaveOffset(R1) // save depth in old g stack (can't just save SP, as stack might be copied during a callback) +#ifdef GOOS_aix + MOVD R7, 0(R1) // Save frame pointer to allow manual backtrace with gdb +#else + MOVD R0, 0(R1) // clear back chain pointer (TODO can we give it real back trace information?) +#endif + // This is a "global call", so put the global entry point in r12 + MOVD R3, R12 + +#ifdef GOARCH_ppc64 + // ppc64 use elf ABI v1. we must get the real entry address from + // first slot of the function descriptor before call. + // Same for AIX. + MOVD 8(R12), R2 + MOVD (R12), R12 +#endif + MOVD R12, CTR + MOVD R4, R3 // arg in r3 + BL (CTR) + // C code can clobber R0, so set it back to 0. F27-F31 are + // callee save, so we don't need to recover those. + XOR R0, R0 + // Restore g, stack pointer, toc pointer. + // R3 is errno, so don't touch it + MOVD (asmcgocallSaveOffset+8)(R1), g + MOVD (g_stack+stack_hi)(g), R5 + MOVD asmcgocallSaveOffset(R1), R6 + SUB R6, R5 +#ifndef GOOS_aix + MOVD 24(R5), R2 +#endif + MOVD R5, R1 + BL runtime·save_g(SB) + + MOVW R3, ret+16(FP) + RET + +// 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. + MOVBZ runtime·iscgo(SB), R3 + CMP R3, $0 + BEQ 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. + CMP g, $0 + BEQ 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), R12 + MOVD R12, CTR + BL (CTR) + + // 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 R1, (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 R1, (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+FIXED_FRAME)(R4) // "saved LR"; must match frame size + // Gather our arguments into registers. + MOVD fn+0(FP), R5 + MOVD frame+8(FP), R6 + MOVD ctxt+16(FP), R7 + MOVD $-(24+FIXED_FRAME)(R4), R1 // switch stack; must match frame size + MOVD R5, FIXED_FRAME+0(R1) + MOVD R6, FIXED_FRAME+8(R1) + MOVD R7, FIXED_FRAME+16(R1) + BL runtime·cgocallbackg(SB) + + // Restore g->sched (== m->curg->sched) from saved values. + MOVD 0(R1), R5 + MOVD R5, (g_sched+gobuf_pc)(g) + MOVD $(24+FIXED_FRAME)(R1), 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), R1 + 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 + CMP R6, $0 + BNE droppedm + MOVD $runtime·dropm(SB), R12 + MOVD R12, CTR + BL (CTR) +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 + +#ifdef GOARCH_ppc64 +#ifdef GOOS_aix +DATA setg_gcc<>+0(SB)/8, $_setg_gcc<>(SB) +DATA setg_gcc<>+8(SB)/8, $TOC(SB) +DATA setg_gcc<>+16(SB)/8, $0 +GLOBL setg_gcc<>(SB), NOPTR, $24 +#else +TEXT setg_gcc<>(SB),NOSPLIT|NOFRAME,$0-0 + DWORD $_setg_gcc<>(SB) + DWORD $0 + DWORD $0 +#endif +#endif + +// void setg_gcc(G*); set g in C TLS. +// Must obey the gcc calling convention. +#ifdef GOARCH_ppc64le +TEXT setg_gcc<>(SB),NOSPLIT|NOFRAME,$0-0 +#else +TEXT _setg_gcc<>(SB),NOSPLIT|NOFRAME,$0-0 +#endif + // The standard prologue clobbers R31, which is callee-save in + // the C ABI, so we have to use $-8-0 and save LR ourselves. + MOVD LR, R4 + // Also save g and R31, since they're callee-save in C ABI + MOVD R31, R5 + MOVD g, R6 + + MOVD R3, g + BL runtime·save_g(SB) + + MOVD R6, g + MOVD R5, R31 + MOVD R4, LR + RET + +TEXT runtime·abort(SB),NOSPLIT|NOFRAME,$0-0 + MOVW (R0), R0 + UNDEF + +#define TBR 268 + +// int64 runtime·cputicks(void) +TEXT runtime·cputicks(SB),NOSPLIT,$0-8 + MOVD SPR(TBR), R3 + MOVD R3, ret+0(FP) + RET + +// AES hashing not implemented for ppc64 +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. +#ifdef GOOS_aix +// On AIX, _cgo_topofstack is defined in runtime/cgo, because it must +// be a longcall in order to prevent trampolines from ld. +TEXT __cgo_topofstack(SB),NOSPLIT|NOFRAME,$0 +#else +TEXT _cgo_topofstack(SB),NOSPLIT|NOFRAME,$0 +#endif + // g (R30) and R31 are callee-save in the C ABI, so save them + MOVD g, R4 + MOVD R31, R5 + MOVD LR, R6 + + BL runtime·load_g(SB) // clobbers g (R30), R31 + MOVD g_m(g), R3 + MOVD m_curg(R3), R3 + MOVD (g_stack+stack_hi)(R3), R3 + + MOVD R4, g + MOVD R5, R31 + MOVD R6, LR + RET + +// The top-most function running on a goroutine +// returns to goexit+PCQuantum. +// +// When dynamically linking Go, it can be returned to from a function +// implemented in a different module and so needs to reload the TOC pointer +// from the stack (although this function declares that it does not set up x-a +// frame, newproc1 does in fact allocate one for goexit and saves the TOC +// pointer in the correct place). +// goexit+_PCQuantum is halfway through the usual global entry point prologue +// that derives r2 from r12 which is a bit silly, but not harmful. +TEXT runtime·goexit(SB),NOSPLIT|NOFRAME|TOPFRAME,$0-0 + MOVD 24(R1), R2 + BL runtime·goexit1(SB) // does not return + // traceback from goexit1 must hit code range of goexit + MOVD R0, R0 // NOP + +// prepGoExitFrame saves the current TOC pointer (i.e. the TOC pointer for the +// module containing runtime) to the frame that goexit will execute in when +// the goroutine exits. It's implemented in assembly mainly because that's the +// easiest way to get access to R2. +TEXT runtime·prepGoExitFrame(SB),NOSPLIT,$0-8 + MOVD sp+0(FP), R3 + MOVD R2, 24(R3) + RET + +TEXT runtime·addmoduledata(SB),NOSPLIT|NOFRAME,$0-0 + ADD $-8, R1 + MOVD R31, 0(R1) + MOVD runtime·lastmoduledatap(SB), R4 + MOVD R3, moduledata_next(R4) + MOVD R3, runtime·lastmoduledatap(SB) + MOVD 0(R1), R31 + ADD $8, R1 + RET + +TEXT ·checkASM(SB),NOSPLIT,$0-1 + MOVW $1, R3 + MOVB R3, 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: +// - R20 is the destination of the write +// - R21 is the value being written at R20. +// It clobbers condition codes. +// It does not clobber R0 through R17 (except special registers), +// but may clobber any other register, *including* R31. +TEXT runtime·gcWriteBarrier(SB),NOSPLIT,$112 + // The standard prologue clobbers R31. + // We use R18 and R19 as scratch registers. + MOVD g_m(g), R18 + MOVD m_p(R18), R18 + MOVD (p_wbBuf+wbBuf_next)(R18), R19 + // Increment wbBuf.next position. + ADD $16, R19 + MOVD R19, (p_wbBuf+wbBuf_next)(R18) + MOVD (p_wbBuf+wbBuf_end)(R18), R18 + CMP R18, R19 + // Record the write. + MOVD R21, -16(R19) // Record value + MOVD (R20), R18 // TODO: This turns bad writes into bad reads. + MOVD R18, -8(R19) // Record *slot + // Is the buffer full? (flags set in CMP above) + BEQ flush +ret: + // Do the write. + MOVD R21, (R20) + RET + +flush: + // Save registers R0 through R15 since these were not saved by the caller. + // We don't save all registers on ppc64 because it takes too much space. + MOVD R20, (FIXED_FRAME+0)(R1) // Also first argument to wbBufFlush + MOVD R21, (FIXED_FRAME+8)(R1) // Also second argument to wbBufFlush + // R0 is always 0, so no need to spill. + // R1 is SP. + // R2 is SB. + MOVD R3, (FIXED_FRAME+16)(R1) + MOVD R4, (FIXED_FRAME+24)(R1) + MOVD R5, (FIXED_FRAME+32)(R1) + MOVD R6, (FIXED_FRAME+40)(R1) + MOVD R7, (FIXED_FRAME+48)(R1) + MOVD R8, (FIXED_FRAME+56)(R1) + MOVD R9, (FIXED_FRAME+64)(R1) + MOVD R10, (FIXED_FRAME+72)(R1) + // R11, R12 may be clobbered by external-linker-inserted trampoline + // R13 is REGTLS + MOVD R14, (FIXED_FRAME+80)(R1) + MOVD R15, (FIXED_FRAME+88)(R1) + MOVD R16, (FIXED_FRAME+96)(R1) + MOVD R17, (FIXED_FRAME+104)(R1) + + // This takes arguments R20 and R21. + CALL runtime·wbBufFlush(SB) + + MOVD (FIXED_FRAME+0)(R1), R20 + MOVD (FIXED_FRAME+8)(R1), R21 + MOVD (FIXED_FRAME+16)(R1), R3 + MOVD (FIXED_FRAME+24)(R1), R4 + MOVD (FIXED_FRAME+32)(R1), R5 + MOVD (FIXED_FRAME+40)(R1), R6 + MOVD (FIXED_FRAME+48)(R1), R7 + MOVD (FIXED_FRAME+56)(R1), R8 + MOVD (FIXED_FRAME+64)(R1), R9 + MOVD (FIXED_FRAME+72)(R1), R10 + MOVD (FIXED_FRAME+80)(R1), R14 + MOVD (FIXED_FRAME+88)(R1), R15 + MOVD (FIXED_FRAME+96)(R1), R16 + MOVD (FIXED_FRAME+104)(R1), R17 + 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 R3, x+0(FP) + MOVD R4, y+8(FP) + JMP runtime·goPanicIndex(SB) +TEXT runtime·panicIndexU(SB),NOSPLIT,$0-16 + MOVD R3, x+0(FP) + MOVD R4, y+8(FP) + JMP runtime·goPanicIndexU(SB) +TEXT runtime·panicSliceAlen(SB),NOSPLIT,$0-16 + MOVD R4, x+0(FP) + MOVD R5, y+8(FP) + JMP runtime·goPanicSliceAlen(SB) +TEXT runtime·panicSliceAlenU(SB),NOSPLIT,$0-16 + MOVD R4, x+0(FP) + MOVD R5, y+8(FP) + JMP runtime·goPanicSliceAlenU(SB) +TEXT runtime·panicSliceAcap(SB),NOSPLIT,$0-16 + MOVD R4, x+0(FP) + MOVD R5, y+8(FP) + JMP runtime·goPanicSliceAcap(SB) +TEXT runtime·panicSliceAcapU(SB),NOSPLIT,$0-16 + MOVD R4, x+0(FP) + MOVD R5, y+8(FP) + JMP runtime·goPanicSliceAcapU(SB) +TEXT runtime·panicSliceB(SB),NOSPLIT,$0-16 + MOVD R3, x+0(FP) + MOVD R4, y+8(FP) + JMP runtime·goPanicSliceB(SB) +TEXT runtime·panicSliceBU(SB),NOSPLIT,$0-16 + MOVD R3, x+0(FP) + MOVD R4, y+8(FP) + JMP runtime·goPanicSliceBU(SB) +TEXT runtime·panicSlice3Alen(SB),NOSPLIT,$0-16 + MOVD R5, x+0(FP) + MOVD R6, y+8(FP) + JMP runtime·goPanicSlice3Alen(SB) +TEXT runtime·panicSlice3AlenU(SB),NOSPLIT,$0-16 + MOVD R5, x+0(FP) + MOVD R6, y+8(FP) + JMP runtime·goPanicSlice3AlenU(SB) +TEXT runtime·panicSlice3Acap(SB),NOSPLIT,$0-16 + MOVD R5, x+0(FP) + MOVD R6, y+8(FP) + JMP runtime·goPanicSlice3Acap(SB) +TEXT runtime·panicSlice3AcapU(SB),NOSPLIT,$0-16 + MOVD R5, x+0(FP) + MOVD R6, y+8(FP) + JMP runtime·goPanicSlice3AcapU(SB) +TEXT runtime·panicSlice3B(SB),NOSPLIT,$0-16 + MOVD R4, x+0(FP) + MOVD R5, y+8(FP) + JMP runtime·goPanicSlice3B(SB) +TEXT runtime·panicSlice3BU(SB),NOSPLIT,$0-16 + MOVD R4, x+0(FP) + MOVD R5, y+8(FP) + JMP runtime·goPanicSlice3BU(SB) +TEXT runtime·panicSlice3C(SB),NOSPLIT,$0-16 + MOVD R3, x+0(FP) + MOVD R4, y+8(FP) + JMP runtime·goPanicSlice3C(SB) +TEXT runtime·panicSlice3CU(SB),NOSPLIT,$0-16 + MOVD R3, x+0(FP) + MOVD R4, y+8(FP) + JMP runtime·goPanicSlice3CU(SB) |