diff options
Diffstat (limited to 'src/runtime/asm_mipsx.s')
| -rw-r--r-- | src/runtime/asm_mipsx.s | 206 |
1 files changed, 188 insertions, 18 deletions
diff --git a/src/runtime/asm_mipsx.s b/src/runtime/asm_mipsx.s index cd855c7d34..73da768897 100644 --- a/src/runtime/asm_mipsx.s +++ b/src/runtime/asm_mipsx.s @@ -12,11 +12,11 @@ #define REGCTXT R22 TEXT runtime·rt0_go(SB),NOSPLIT,$0 - // R29 = stack; R1 = argc; R2 = argv + // R29 = stack; R4 = argc; R5 = argv ADDU $-12, R29 - MOVW R1, 4(R29) // argc - MOVW R2, 8(R29) // argv + MOVW R4, 4(R29) // argc + MOVW R5, 8(R29) // argv // create istack out of the given (operating system) stack. // _cgo_init may update stackguard. @@ -28,7 +28,16 @@ TEXT runtime·rt0_go(SB),NOSPLIT,$0 MOVW R1, (g_stack+stack_lo)(g) MOVW R29, (g_stack+stack_hi)(g) -// TODO(mips32): cgo + // if there is a _cgo_init, call it using the gcc ABI. + MOVW _cgo_init(SB), R25 + BEQ R25, nocgo + ADDU $-16, R29 + MOVW R0, R7 // arg 3: not used + MOVW R0, R6 // arg 2: not used + MOVW $setg_gcc<>(SB), R5 // arg 1: setg + MOVW g, R4 // arg 0: G + JAL (R25) + ADDU $16, R29 nocgo: // update stackguard after _cgo_init @@ -434,7 +443,7 @@ TEXT runtime·jmpdefer(SB),NOSPLIT,$0-8 JMP (R4) // Save state of caller into g->sched. Smashes R1. -TEXT gosave<>(SB),NOSPLIT,$0 +TEXT gosave<>(SB),NOSPLIT,$-4 MOVW R31, (g_sched+gobuf_pc)(g) MOVW R29, (g_sched+gobuf_sp)(g) MOVW R0, (g_sched+gobuf_lr)(g) @@ -449,22 +458,168 @@ TEXT gosave<>(SB),NOSPLIT,$0 // Call fn(arg) on the scheduler stack, // aligned appropriately for the gcc ABI. // See cgocall.go for more details. -// Not implemented. TEXT ·asmcgocall(SB),NOSPLIT,$0-12 - UNDEF + MOVW fn+0(FP), R25 + MOVW arg+4(FP), R4 + + MOVW R29, R3 // save original stack pointer + MOVW g, R2 + + // 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. + MOVW g_m(g), R5 + MOVW m_g0(R5), R6 + BEQ R6, g, g0 + + JAL gosave<>(SB) + MOVW R6, g + JAL runtime·save_g(SB) + MOVW (g_sched+gobuf_sp)(g), R29 + + // Now on a scheduling stack (a pthread-created stack). +g0: + // Save room for two of our pointers and O32 frame. + ADDU $-24, R29 + AND $~7, R29 // O32 ABI expects 8-byte aligned stack on function entry + MOVW R2, 16(R29) // save old g on stack + MOVW (g_stack+stack_hi)(R2), R2 + SUBU R3, R2 + MOVW R2, 20(R29) // save depth in old g stack (can't just save SP, as stack might be copied during a callback) + JAL (R25) + + // Restore g, stack pointer. R2 is return value. + MOVW 16(R29), g + JAL runtime·save_g(SB) + MOVW (g_stack+stack_hi)(g), R5 + MOVW 20(R29), R6 + SUBU R6, R5 + MOVW R5, R29 + + MOVW R2, ret+8(FP) + RET // cgocallback(void (*fn)(void*), void *frame, uintptr framesize) // Turn the fn into a Go func (by taking its address) and call // cgocallback_gofunc. -// Not implemented. -TEXT runtime·cgocallback(SB),NOSPLIT,$0-16 - UNDEF +TEXT runtime·cgocallback(SB),NOSPLIT,$16-16 + MOVW $fn+0(FP), R1 + MOVW R1, 4(R29) + MOVW frame+4(FP), R1 + MOVW R1, 8(R29) + MOVW framesize+8(FP), R1 + MOVW R1, 12(R29) + MOVW ctxt+12(FP), R1 + MOVW R1, 16(R29) + MOVW $runtime·cgocallback_gofunc(SB), R1 + JAL (R1) + RET -// cgocallback_gofunc(FuncVal*, void *frame, uintptr framesize) +// cgocallback_gofunc(FuncVal*, void *frame, uintptr framesize, uintptr ctxt) // See cgocall.go for more details. -// Not implemented. -TEXT ·cgocallback_gofunc(SB),NOSPLIT,$0-16 - UNDEF +TEXT ·cgocallback_gofunc(SB),NOSPLIT,$8-16 + NO_LOCAL_POINTERS + + // Load m and g from thread-local storage. + MOVB runtime·iscgo(SB), R1 + BEQ R1, nocgo + JAL 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 g, needm + + MOVW g_m(g), R3 + MOVW R3, savedm-4(SP) + JMP havem + +needm: + MOVW g, savedm-4(SP) // g is zero, so is m. + MOVW $runtime·needm(SB), R4 + JAL (R4) + + // 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. + MOVW g_m(g), R3 + MOVW m_g0(R3), R1 + MOVW R29, (g_sched+gobuf_sp)(R1) + +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 4(R29) aka savedsp-8(SP). + MOVW m_g0(R3), R1 + MOVW (g_sched+gobuf_sp)(R1), R2 + MOVW R2, savedsp-8(SP) + MOVW R29, (g_sched+gobuf_sp)(R1) + + // 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 stack. + // This has the added benefit that it looks to the traceback + // routine like cgocallbackg is going to return to that + // PC (because the frame we allocate below has the same + // size as cgocallback_gofunc's frame declared above) + // so that the traceback will seamlessly trace back into + // the earlier calls. + // + // In the new goroutine, -4(SP) is unused (where SP refers to + // m->curg's SP while we're setting it up, before we've adjusted it). + MOVW m_curg(R3), g + JAL runtime·save_g(SB) + MOVW (g_sched+gobuf_sp)(g), R2 // prepare stack as R2 + MOVW (g_sched+gobuf_pc)(g), R4 + MOVW R4, -12(R2) + MOVW ctxt+12(FP), R1 + MOVW R1, -8(R2) + MOVW $-12(R2), R29 + JAL runtime·cgocallbackg(SB) + + // Restore g->sched (== m->curg->sched) from saved values. + MOVW 0(R29), R4 + MOVW R4, (g_sched+gobuf_pc)(g) + MOVW $12(R29), R2 + MOVW R2, (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.) + MOVW g_m(g), R3 + MOVW m_g0(R3), g + JAL runtime·save_g(SB) + MOVW (g_sched+gobuf_sp)(g), R29 + MOVW savedsp-8(SP), R2 + MOVW R2, (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. + MOVW savedm-4(SP), R3 + BNE R3, droppedm + MOVW $runtime·dropm(SB), R4 + JAL (R4) +droppedm: + + // Done! + RET // void setg(G*); set g. for use by needm. // This only happens if iscgo, so jump straight to save_g @@ -475,9 +630,10 @@ TEXT runtime·setg(SB),NOSPLIT,$0-4 // void setg_gcc(G*); set g in C TLS. // Must obey the gcc calling convention. -// Not implemented. TEXT setg_gcc<>(SB),NOSPLIT,$0 - UNDEF + MOVW R4, g + JAL runtime·save_g(SB) + RET TEXT runtime·getcallerpc(SB),NOSPLIT,$4-8 MOVW 8(R29), R1 // LR saved by caller @@ -764,9 +920,23 @@ TEXT runtime·return0(SB),NOSPLIT,$0 // Called from cgo wrappers, this function returns g->m->curg.stack.hi. // Must obey the gcc calling convention. -// Not implemented. TEXT _cgo_topofstack(SB),NOSPLIT,$-4 - UNDEF + // g (R30), R3 and REGTMP (R23) might be clobbered by load_g. R30 and R23 + // are callee-save in the gcc calling convention, so save them. + MOVW R23, R8 + MOVW g, R9 + MOVW R31, R10 // this call frame does not save LR + + JAL runtime·load_g(SB) + MOVW g_m(g), R1 + MOVW m_curg(R1), R1 + MOVW (g_stack+stack_hi)(R1), R2 // return value in R2 + + MOVW R8, R23 + MOVW R9, g + MOVW R10, R31 + + RET // The top-most function running on a goroutine // returns to goexit+PCQuantum. |