// Copyright 2016 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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#include "go_asm.h"
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#include "go_tls.h"
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#include "funcdata.h"
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#include "textflag.h"
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// _rt0_s390x_lib is common startup code for s390x systems when
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// using -buildmode=c-archive or -buildmode=c-shared. The linker will
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// arrange to invoke this function as a global constructor (for
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// c-archive) or when the shared library is loaded (for c-shared).
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// We expect argc and argv to be passed in the usual C ABI registers
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// R2 and R3.
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TEXT _rt0_s390x_lib(SB), NOSPLIT|NOFRAME, $0
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STMG R6, R15, 48(R15)
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MOVD R2, _rt0_s390x_lib_argc<>(SB)
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MOVD R3, _rt0_s390x_lib_argv<>(SB)
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// Save R6-R15 in the register save area of the calling function.
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STMG R6, R15, 48(R15)
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// Allocate 80 bytes on the stack.
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MOVD $-80(R15), R15
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// Save F8-F15 in our stack frame.
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FMOVD F8, 16(R15)
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FMOVD F9, 24(R15)
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FMOVD F10, 32(R15)
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FMOVD F11, 40(R15)
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FMOVD F12, 48(R15)
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FMOVD F13, 56(R15)
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FMOVD F14, 64(R15)
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FMOVD F15, 72(R15)
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// Synchronous initialization.
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MOVD $runtime·libpreinit(SB), R1
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BL R1
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// Create a new thread to finish Go runtime initialization.
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MOVD _cgo_sys_thread_create(SB), R1
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CMP R1, $0
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BEQ nocgo
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MOVD $_rt0_s390x_lib_go(SB), R2
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MOVD $0, R3
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BL R1
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BR restore
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nocgo:
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MOVD $0x800000, R1 // stacksize
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MOVD R1, 0(R15)
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MOVD $_rt0_s390x_lib_go(SB), R1
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MOVD R1, 8(R15) // fn
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MOVD $runtime·newosproc(SB), R1
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BL R1
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restore:
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// Restore F8-F15 from our stack frame.
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FMOVD 16(R15), F8
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FMOVD 24(R15), F9
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FMOVD 32(R15), F10
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FMOVD 40(R15), F11
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FMOVD 48(R15), F12
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FMOVD 56(R15), F13
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FMOVD 64(R15), F14
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FMOVD 72(R15), F15
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MOVD $80(R15), R15
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// Restore R6-R15.
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LMG 48(R15), R6, R15
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RET
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// _rt0_s390x_lib_go initializes the Go runtime.
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// This is started in a separate thread by _rt0_s390x_lib.
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TEXT _rt0_s390x_lib_go(SB), NOSPLIT|NOFRAME, $0
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MOVD _rt0_s390x_lib_argc<>(SB), R2
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MOVD _rt0_s390x_lib_argv<>(SB), R3
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MOVD $runtime·rt0_go(SB), R1
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BR R1
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DATA _rt0_s390x_lib_argc<>(SB)/8, $0
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GLOBL _rt0_s390x_lib_argc<>(SB), NOPTR, $8
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DATA _rt0_s90x_lib_argv<>(SB)/8, $0
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GLOBL _rt0_s390x_lib_argv<>(SB), NOPTR, $8
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TEXT runtime·rt0_go(SB),NOSPLIT,$0
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// R2 = argc; R3 = argv; R11 = temp; R13 = g; R15 = stack pointer
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// C TLS base pointer in AR0:AR1
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// initialize essential registers
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XOR R0, R0
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SUB $24, R15
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MOVW R2, 8(R15) // argc
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MOVD R3, 16(R15) // argv
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// create istack out of the given (operating system) stack.
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// _cgo_init may update stackguard.
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MOVD $runtime·g0(SB), g
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MOVD R15, R11
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SUB $(64*1024), R11
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MOVD R11, g_stackguard0(g)
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MOVD R11, g_stackguard1(g)
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MOVD R11, (g_stack+stack_lo)(g)
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MOVD R15, (g_stack+stack_hi)(g)
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// if there is a _cgo_init, call it using the gcc ABI.
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MOVD _cgo_init(SB), R11
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CMPBEQ R11, $0, nocgo
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MOVW AR0, R4 // (AR0 << 32 | AR1) is the TLS base pointer; MOVD is translated to EAR
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SLD $32, R4, R4
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MOVW AR1, R4 // arg 2: TLS base pointer
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MOVD $setg_gcc<>(SB), R3 // arg 1: setg
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MOVD g, R2 // arg 0: G
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// C functions expect 160 bytes of space on caller stack frame
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// and an 8-byte aligned stack pointer
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MOVD R15, R9 // save current stack (R9 is preserved in the Linux ABI)
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SUB $160, R15 // reserve 160 bytes
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MOVD $~7, R6
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AND R6, R15 // 8-byte align
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BL R11 // this call clobbers volatile registers according to Linux ABI (R0-R5, R14)
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MOVD R9, R15 // restore stack
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XOR R0, R0 // zero R0
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nocgo:
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// update stackguard after _cgo_init
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MOVD (g_stack+stack_lo)(g), R2
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ADD $const__StackGuard, R2
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MOVD R2, g_stackguard0(g)
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MOVD R2, g_stackguard1(g)
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// set the per-goroutine and per-mach "registers"
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MOVD $runtime·m0(SB), R2
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// save m->g0 = g0
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MOVD g, m_g0(R2)
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// save m0 to g0->m
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MOVD R2, g_m(g)
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BL runtime·check(SB)
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// argc/argv are already prepared on stack
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BL runtime·args(SB)
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BL runtime·osinit(SB)
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BL runtime·schedinit(SB)
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// create a new goroutine to start program
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MOVD $runtime·mainPC(SB), R2 // entry
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SUB $24, R15
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MOVD R2, 16(R15)
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MOVD $0, 8(R15)
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MOVD $0, 0(R15)
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BL runtime·newproc(SB)
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ADD $24, R15
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// start this M
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BL runtime·mstart(SB)
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MOVD $0, 1(R0)
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RET
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DATA runtime·mainPC+0(SB)/8,$runtime·main(SB)
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GLOBL runtime·mainPC(SB),RODATA,$8
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TEXT runtime·breakpoint(SB),NOSPLIT|NOFRAME,$0-0
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MOVD $0, 2(R0)
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RET
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TEXT runtime·asminit(SB),NOSPLIT|NOFRAME,$0-0
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RET
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/*
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* go-routine
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*/
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// void gosave(Gobuf*)
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// save state in Gobuf; setjmp
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TEXT runtime·gosave(SB), NOSPLIT, $-8-8
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MOVD buf+0(FP), R3
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MOVD R15, gobuf_sp(R3)
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MOVD LR, gobuf_pc(R3)
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MOVD g, gobuf_g(R3)
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MOVD $0, gobuf_lr(R3)
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MOVD $0, gobuf_ret(R3)
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// Assert ctxt is zero. See func save.
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MOVD gobuf_ctxt(R3), R3
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CMPBEQ R3, $0, 2(PC)
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BL runtime·badctxt(SB)
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RET
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// void gogo(Gobuf*)
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// restore state from Gobuf; longjmp
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TEXT runtime·gogo(SB), NOSPLIT, $16-8
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MOVD buf+0(FP), R5
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MOVD gobuf_g(R5), g // make sure g is not nil
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BL runtime·save_g(SB)
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MOVD 0(g), R4
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MOVD gobuf_sp(R5), R15
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MOVD gobuf_lr(R5), LR
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MOVD gobuf_ret(R5), R3
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MOVD gobuf_ctxt(R5), R12
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MOVD $0, gobuf_sp(R5)
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MOVD $0, gobuf_ret(R5)
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MOVD $0, gobuf_lr(R5)
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MOVD $0, gobuf_ctxt(R5)
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CMP R0, R0 // set condition codes for == test, needed by stack split
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MOVD gobuf_pc(R5), R6
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BR (R6)
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// void mcall(fn func(*g))
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// Switch to m->g0's stack, call fn(g).
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// Fn must never return. It should gogo(&g->sched)
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// to keep running g.
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TEXT runtime·mcall(SB), NOSPLIT, $-8-8
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// Save caller state in g->sched
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MOVD R15, (g_sched+gobuf_sp)(g)
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MOVD LR, (g_sched+gobuf_pc)(g)
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MOVD $0, (g_sched+gobuf_lr)(g)
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MOVD g, (g_sched+gobuf_g)(g)
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// Switch to m->g0 & its stack, call fn.
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MOVD g, R3
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MOVD g_m(g), R8
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MOVD m_g0(R8), g
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BL runtime·save_g(SB)
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CMP g, R3
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BNE 2(PC)
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BR runtime·badmcall(SB)
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MOVD fn+0(FP), R12 // context
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MOVD 0(R12), R4 // code pointer
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MOVD (g_sched+gobuf_sp)(g), R15 // sp = m->g0->sched.sp
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SUB $16, R15
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MOVD R3, 8(R15)
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MOVD $0, 0(R15)
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BL (R4)
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BR runtime·badmcall2(SB)
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// systemstack_switch is a dummy routine that systemstack leaves at the bottom
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// of the G stack. We need to distinguish the routine that
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// lives at the bottom of the G stack from the one that lives
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// at the top of the system stack because the one at the top of
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// the system stack terminates the stack walk (see topofstack()).
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TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0
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UNDEF
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BL (LR) // make sure this function is not leaf
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RET
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// func systemstack(fn func())
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TEXT runtime·systemstack(SB), NOSPLIT, $0-8
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MOVD fn+0(FP), R3 // R3 = fn
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MOVD R3, R12 // context
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MOVD g_m(g), R4 // R4 = m
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MOVD m_gsignal(R4), R5 // R5 = gsignal
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CMPBEQ g, R5, noswitch
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MOVD m_g0(R4), R5 // R5 = g0
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CMPBEQ g, R5, noswitch
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MOVD m_curg(R4), R6
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CMPBEQ g, R6, switch
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// Bad: g is not gsignal, not g0, not curg. What is it?
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// Hide call from linker nosplit analysis.
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MOVD $runtime·badsystemstack(SB), R3
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BL (R3)
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BL runtime·abort(SB)
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switch:
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// save our state in g->sched. Pretend to
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// be systemstack_switch if the G stack is scanned.
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MOVD $runtime·systemstack_switch(SB), R6
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ADD $16, R6 // get past prologue
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MOVD R6, (g_sched+gobuf_pc)(g)
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MOVD R15, (g_sched+gobuf_sp)(g)
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MOVD $0, (g_sched+gobuf_lr)(g)
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MOVD g, (g_sched+gobuf_g)(g)
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// switch to g0
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MOVD R5, g
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BL runtime·save_g(SB)
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MOVD (g_sched+gobuf_sp)(g), R3
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// make it look like mstart called systemstack on g0, to stop traceback
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SUB $8, R3
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MOVD $runtime·mstart(SB), R4
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MOVD R4, 0(R3)
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MOVD R3, R15
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// call target function
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MOVD 0(R12), R3 // code pointer
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BL (R3)
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// switch back to g
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MOVD g_m(g), R3
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MOVD m_curg(R3), g
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BL runtime·save_g(SB)
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MOVD (g_sched+gobuf_sp)(g), R15
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MOVD $0, (g_sched+gobuf_sp)(g)
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RET
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noswitch:
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// already on m stack, just call directly
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// Using a tail call here cleans up tracebacks since we won't stop
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// at an intermediate systemstack.
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MOVD 0(R12), R3 // code pointer
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MOVD 0(R15), LR // restore LR
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ADD $8, R15
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BR (R3)
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/*
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* support for morestack
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*/
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// Called during function prolog when more stack is needed.
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// Caller has already loaded:
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// R3: framesize, R4: argsize, R5: LR
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//
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// The traceback routines see morestack on a g0 as being
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// the top of a stack (for example, morestack calling newstack
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// calling the scheduler calling newm calling gc), so we must
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// record an argument size. For that purpose, it has no arguments.
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TEXT runtime·morestack(SB),NOSPLIT|NOFRAME,$0-0
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// Cannot grow scheduler stack (m->g0).
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MOVD g_m(g), R7
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MOVD m_g0(R7), R8
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CMPBNE g, R8, 3(PC)
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BL runtime·badmorestackg0(SB)
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BL runtime·abort(SB)
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// Cannot grow signal stack (m->gsignal).
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MOVD m_gsignal(R7), R8
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CMP g, R8
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BNE 3(PC)
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BL runtime·badmorestackgsignal(SB)
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BL runtime·abort(SB)
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// Called from f.
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// Set g->sched to context in f.
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MOVD R15, (g_sched+gobuf_sp)(g)
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MOVD LR, R8
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MOVD R8, (g_sched+gobuf_pc)(g)
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MOVD R5, (g_sched+gobuf_lr)(g)
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MOVD R12, (g_sched+gobuf_ctxt)(g)
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// Called from f.
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// Set m->morebuf to f's caller.
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MOVD R5, (m_morebuf+gobuf_pc)(R7) // f's caller's PC
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MOVD R15, (m_morebuf+gobuf_sp)(R7) // f's caller's SP
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MOVD g, (m_morebuf+gobuf_g)(R7)
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// Call newstack on m->g0's stack.
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MOVD m_g0(R7), g
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BL runtime·save_g(SB)
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MOVD (g_sched+gobuf_sp)(g), R15
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// Create a stack frame on g0 to call newstack.
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MOVD $0, -8(R15) // Zero saved LR in frame
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SUB $8, R15
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BL runtime·newstack(SB)
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// Not reached, but make sure the return PC from the call to newstack
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// is still in this function, and not the beginning of the next.
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UNDEF
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TEXT runtime·morestack_noctxt(SB),NOSPLIT|NOFRAME,$0-0
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MOVD $0, R12
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BR runtime·morestack(SB)
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// reflectcall: call a function with the given argument list
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// func call(argtype *_type, f *FuncVal, arg *byte, argsize, retoffset uint32).
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// we don't have variable-sized frames, so we use a small number
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// of constant-sized-frame functions to encode a few bits of size in the pc.
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// Caution: ugly multiline assembly macros in your future!
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#define DISPATCH(NAME,MAXSIZE) \
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MOVD $MAXSIZE, R4; \
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CMP R3, R4; \
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BGT 3(PC); \
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MOVD $NAME(SB), R5; \
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BR (R5)
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// Note: can't just "BR NAME(SB)" - bad inlining results.
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TEXT ·reflectcall(SB), NOSPLIT, $-8-32
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MOVWZ argsize+24(FP), R3
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DISPATCH(runtime·call32, 32)
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DISPATCH(runtime·call64, 64)
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DISPATCH(runtime·call128, 128)
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DISPATCH(runtime·call256, 256)
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DISPATCH(runtime·call512, 512)
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DISPATCH(runtime·call1024, 1024)
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DISPATCH(runtime·call2048, 2048)
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DISPATCH(runtime·call4096, 4096)
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DISPATCH(runtime·call8192, 8192)
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DISPATCH(runtime·call16384, 16384)
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DISPATCH(runtime·call32768, 32768)
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DISPATCH(runtime·call65536, 65536)
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DISPATCH(runtime·call131072, 131072)
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DISPATCH(runtime·call262144, 262144)
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DISPATCH(runtime·call524288, 524288)
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DISPATCH(runtime·call1048576, 1048576)
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DISPATCH(runtime·call2097152, 2097152)
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DISPATCH(runtime·call4194304, 4194304)
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DISPATCH(runtime·call8388608, 8388608)
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DISPATCH(runtime·call16777216, 16777216)
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DISPATCH(runtime·call33554432, 33554432)
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DISPATCH(runtime·call67108864, 67108864)
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DISPATCH(runtime·call134217728, 134217728)
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DISPATCH(runtime·call268435456, 268435456)
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DISPATCH(runtime·call536870912, 536870912)
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DISPATCH(runtime·call1073741824, 1073741824)
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MOVD $runtime·badreflectcall(SB), R5
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BR (R5)
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#define CALLFN(NAME,MAXSIZE) \
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TEXT NAME(SB), WRAPPER, $MAXSIZE-24; \
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NO_LOCAL_POINTERS; \
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/* copy arguments to stack */ \
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MOVD arg+16(FP), R4; \
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MOVWZ argsize+24(FP), R5; \
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MOVD $stack-MAXSIZE(SP), R6; \
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loopArgs: /* copy 256 bytes at a time */ \
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CMP R5, $256; \
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BLT tailArgs; \
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SUB $256, R5; \
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MVC $256, 0(R4), 0(R6); \
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MOVD $256(R4), R4; \
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MOVD $256(R6), R6; \
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BR loopArgs; \
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tailArgs: /* copy remaining bytes */ \
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CMP R5, $0; \
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BEQ callFunction; \
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SUB $1, R5; \
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EXRL $callfnMVC<>(SB), R5; \
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callFunction: \
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MOVD f+8(FP), R12; \
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MOVD (R12), R8; \
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PCDATA $PCDATA_StackMapIndex, $0; \
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BL (R8); \
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/* copy return values back */ \
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MOVD argtype+0(FP), R7; \
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MOVD arg+16(FP), R6; \
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MOVWZ n+24(FP), R5; \
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MOVD $stack-MAXSIZE(SP), R4; \
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MOVWZ retoffset+28(FP), R1; \
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ADD R1, R4; \
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ADD R1, R6; \
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SUB R1, R5; \
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BL callRet<>(SB); \
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RET
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// callRet copies return values back at the end of call*. This is a
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// separate function so it can allocate stack space for the arguments
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// to reflectcallmove. It does not follow the Go ABI; it expects its
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// arguments in registers.
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TEXT callRet<>(SB), NOSPLIT, $32-0
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MOVD R7, 8(R15)
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MOVD R6, 16(R15)
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MOVD R4, 24(R15)
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MOVD R5, 32(R15)
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BL runtime·reflectcallmove(SB)
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RET
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CALLFN(·call32, 32)
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CALLFN(·call64, 64)
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CALLFN(·call128, 128)
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CALLFN(·call256, 256)
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CALLFN(·call512, 512)
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CALLFN(·call1024, 1024)
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CALLFN(·call2048, 2048)
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CALLFN(·call4096, 4096)
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CALLFN(·call8192, 8192)
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CALLFN(·call16384, 16384)
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CALLFN(·call32768, 32768)
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CALLFN(·call65536, 65536)
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CALLFN(·call131072, 131072)
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CALLFN(·call262144, 262144)
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CALLFN(·call524288, 524288)
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CALLFN(·call1048576, 1048576)
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CALLFN(·call2097152, 2097152)
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CALLFN(·call4194304, 4194304)
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CALLFN(·call8388608, 8388608)
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CALLFN(·call16777216, 16777216)
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CALLFN(·call33554432, 33554432)
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CALLFN(·call67108864, 67108864)
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CALLFN(·call134217728, 134217728)
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CALLFN(·call268435456, 268435456)
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CALLFN(·call536870912, 536870912)
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CALLFN(·call1073741824, 1073741824)
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// Not a function: target for EXRL (execute relative long) instruction.
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TEXT callfnMVC<>(SB),NOSPLIT|NOFRAME,$0-0
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MVC $1, 0(R4), 0(R6)
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TEXT runtime·procyield(SB),NOSPLIT,$0-0
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RET
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// void jmpdefer(fv, sp);
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// called from deferreturn.
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// 1. grab stored LR for caller
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// 2. sub 6 bytes to get back to BL deferreturn (size of BRASL instruction)
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// 3. BR to fn
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TEXT runtime·jmpdefer(SB),NOSPLIT|NOFRAME,$0-16
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MOVD 0(R15), R1
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SUB $6, R1, LR
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MOVD fv+0(FP), R12
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MOVD argp+8(FP), R15
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SUB $8, R15
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MOVD 0(R12), R3
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BR (R3)
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// Save state of caller into g->sched. Smashes R1.
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TEXT gosave<>(SB),NOSPLIT|NOFRAME,$0
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MOVD LR, (g_sched+gobuf_pc)(g)
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MOVD R15, (g_sched+gobuf_sp)(g)
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MOVD $0, (g_sched+gobuf_lr)(g)
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MOVD $0, (g_sched+gobuf_ret)(g)
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// Assert ctxt is zero. See func save.
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MOVD (g_sched+gobuf_ctxt)(g), R1
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CMPBEQ R1, $0, 2(PC)
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BL runtime·badctxt(SB)
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RET
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// func asmcgocall(fn, arg unsafe.Pointer) int32
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// Call fn(arg) on the scheduler stack,
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// aligned appropriately for the gcc ABI.
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// See cgocall.go for more details.
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TEXT ·asmcgocall(SB),NOSPLIT,$0-20
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// R2 = argc; R3 = argv; R11 = temp; R13 = g; R15 = stack pointer
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// C TLS base pointer in AR0:AR1
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MOVD fn+0(FP), R3
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MOVD arg+8(FP), R4
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MOVD R15, R2 // save original stack pointer
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MOVD g, R5
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// Figure out if we need to switch to m->g0 stack.
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// We get called to create new OS threads too, and those
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// come in on the m->g0 stack already.
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MOVD g_m(g), R6
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MOVD m_g0(R6), R6
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CMPBEQ R6, g, g0
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BL gosave<>(SB)
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MOVD R6, g
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BL runtime·save_g(SB)
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MOVD (g_sched+gobuf_sp)(g), R15
|
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// 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(void (*fn)(void*), void *frame, uintptr framesize, uintptr ctxt)
|
// Turn the fn into a Go func (by taking its address) and call
|
// cgocallback_gofunc.
|
TEXT runtime·cgocallback(SB),NOSPLIT,$32-32
|
MOVD $fn+0(FP), R3
|
MOVD R3, 8(R15)
|
MOVD frame+8(FP), R3
|
MOVD R3, 16(R15)
|
MOVD framesize+16(FP), R3
|
MOVD R3, 24(R15)
|
MOVD ctxt+24(FP), R3
|
MOVD R3, 32(R15)
|
MOVD $runtime·cgocallback_gofunc(SB), R3
|
BL (R3)
|
RET
|
|
// cgocallback_gofunc(FuncVal*, void *frame, uintptr framesize, uintptr ctxt)
|
// See cgocall.go for more details.
|
TEXT ·cgocallback_gofunc(SB),NOSPLIT,$16-32
|
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-16(SP)
|
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 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, -8(SP) is unused (where SP refers to
|
// m->curg's SP while we're setting it up, before we've adjusted it).
|
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(R4)
|
MOVD ctxt+24(FP), R5
|
MOVD R5, -16(R4)
|
MOVD $-24(R4), 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(R15), R4
|
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-16(SP), R4
|
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·aeshash(SB),NOSPLIT|NOFRAME,$0-0
|
MOVW (R0), R15
|
TEXT runtime·aeshash32(SB),NOSPLIT|NOFRAME,$0-0
|
MOVW (R0), R15
|
TEXT runtime·aeshash64(SB),NOSPLIT|NOFRAME,$0-0
|
MOVW (R0), R15
|
TEXT runtime·aeshashstr(SB),NOSPLIT|NOFRAME,$0-0
|
MOVW (R0), R15
|
|
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,$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 runtime·sigreturn(SB),NOSPLIT,$0-0
|
RET
|
|
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
|
