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Diffstat (limited to 'src/runtime/sys_windows_arm.s')
-rw-r--r-- | src/runtime/sys_windows_arm.s | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/src/runtime/sys_windows_arm.s b/src/runtime/sys_windows_arm.s new file mode 100644 index 0000000..67009df --- /dev/null +++ b/src/runtime/sys_windows_arm.s @@ -0,0 +1,320 @@ +// Copyright 2018 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 "textflag.h" +#include "time_windows.h" + +// Note: For system ABI, R0-R3 are args, R4-R11 are callee-save. + +// void runtime·asmstdcall(void *c); +TEXT runtime·asmstdcall(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R5, R14], (R13) // push {r4, r5, lr} + MOVW R0, R4 // put libcall * in r4 + MOVW R13, R5 // save stack pointer in r5 + + // SetLastError(0) + MOVW $0, R0 + MRC 15, 0, R1, C13, C0, 2 + MOVW R0, 0x34(R1) + + MOVW 8(R4), R12 // libcall->args + + // Do we have more than 4 arguments? + MOVW 4(R4), R0 // libcall->n + SUB.S $4, R0, R2 + BLE loadregs + + // Reserve stack space for remaining args + SUB R2<<2, R13 + BIC $0x7, R13 // alignment for ABI + + // R0: count of arguments + // R1: + // R2: loop counter, from 0 to (n-4) + // R3: scratch + // R4: pointer to libcall struct + // R12: libcall->args + MOVW $0, R2 +stackargs: + ADD $4, R2, R3 // r3 = args[4 + i] + MOVW R3<<2(R12), R3 + MOVW R3, R2<<2(R13) // stack[i] = r3 + + ADD $1, R2 // i++ + SUB $4, R0, R3 // while (i < (n - 4)) + CMP R3, R2 + BLT stackargs + +loadregs: + CMP $3, R0 + MOVW.GT 12(R12), R3 + + CMP $2, R0 + MOVW.GT 8(R12), R2 + + CMP $1, R0 + MOVW.GT 4(R12), R1 + + CMP $0, R0 + MOVW.GT 0(R12), R0 + + BIC $0x7, R13 // alignment for ABI + MOVW 0(R4), R12 // branch to libcall->fn + BL (R12) + + MOVW R5, R13 // free stack space + MOVW R0, 12(R4) // save return value to libcall->r1 + MOVW R1, 16(R4) + + // GetLastError + MRC 15, 0, R1, C13, C0, 2 + MOVW 0x34(R1), R0 + MOVW R0, 20(R4) // store in libcall->err + + MOVM.IA.W (R13), [R4, R5, R15] + +TEXT runtime·getlasterror(SB),NOSPLIT,$0 + MRC 15, 0, R0, C13, C0, 2 + MOVW 0x34(R0), R0 + MOVW R0, ret+0(FP) + RET + +// Called by Windows as a Vectored Exception Handler (VEH). +// R0 is pointer to struct containing +// exception record and context pointers. +// R1 is the kind of sigtramp function. +// Return value of sigtrampgo is stored in R0. +TEXT sigtramp<>(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4-R11, R14], (R13) // push {r4-r11, lr} (SP-=40) + SUB $(16), R13 // reserve space for parameters/retval to go call + + MOVW R0, R6 // Save param0 + MOVW R1, R7 // Save param1 + BL runtime·load_g(SB) // Clobbers R0 + + MOVW $0, R4 + MOVW R4, 0(R13) // No saved link register. + MOVW R6, 4(R13) // Move arg0 into position + MOVW R7, 8(R13) // Move arg1 into position + BL runtime·sigtrampgo(SB) + MOVW 12(R13), R0 // Fetch return value from stack + + ADD $(16), R13 // free locals + MOVM.IA.W (R13), [R4-R11, R14] // pop {r4-r11, lr} + + B (R14) // return + +// Trampoline to resume execution from exception handler. +// This is part of the control flow guard workaround. +// It switches stacks and jumps to the continuation address. +// R0 and R1 are set above at the end of sigtrampgo +// in the context that starts executing at sigresume. +TEXT runtime·sigresume(SB),NOSPLIT|NOFRAME,$0 + // Important: do not smash LR, + // which is set to a live value when handling + // a signal by pushing a call to sigpanic onto the stack. + MOVW R0, R13 + B (R1) + +TEXT runtime·exceptiontramp(SB),NOSPLIT|NOFRAME,$0 + MOVW $const_callbackVEH, R1 + B sigtramp<>(SB) + +TEXT runtime·firstcontinuetramp(SB),NOSPLIT|NOFRAME,$0 + MOVW $const_callbackFirstVCH, R1 + B sigtramp<>(SB) + +TEXT runtime·lastcontinuetramp(SB),NOSPLIT|NOFRAME,$0 + MOVW $const_callbackLastVCH, R1 + B sigtramp<>(SB) + +TEXT runtime·callbackasm1(SB),NOSPLIT|NOFRAME,$0 + // On entry, the trampoline in zcallback_windows_arm.s left + // the callback index in R12 (which is volatile in the C ABI). + + // Push callback register arguments r0-r3. We do this first so + // they're contiguous with stack arguments. + MOVM.DB.W [R0-R3], (R13) + // Push C callee-save registers r4-r11 and lr. + MOVM.DB.W [R4-R11, R14], (R13) + SUB $(16 + callbackArgs__size), R13 // space for locals + + // Create a struct callbackArgs on our stack. + MOVW R12, (16+callbackArgs_index)(R13) // callback index + MOVW $(16+callbackArgs__size+4*9)(R13), R0 + MOVW R0, (16+callbackArgs_args)(R13) // address of args vector + MOVW $0, R0 + MOVW R0, (16+callbackArgs_result)(R13) // result + + // Prepare for entry to Go. + BL runtime·load_g(SB) + + // Call cgocallback, which will call callbackWrap(frame). + MOVW $0, R0 + MOVW R0, 12(R13) // context + MOVW $16(R13), R1 // R1 = &callbackArgs{...} + MOVW R1, 8(R13) // frame (address of callbackArgs) + MOVW $·callbackWrap(SB), R1 + MOVW R1, 4(R13) // PC of function to call + BL runtime·cgocallback(SB) + + // Get callback result. + MOVW (16+callbackArgs_result)(R13), R0 + + ADD $(16 + callbackArgs__size), R13 // free locals + MOVM.IA.W (R13), [R4-R11, R12] // pop {r4-r11, lr=>r12} + ADD $(4*4), R13 // skip r0-r3 + B (R12) // return + +// uint32 tstart_stdcall(M *newm); +TEXT runtime·tstart_stdcall(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4-R11, R14], (R13) // push {r4-r11, lr} + + MOVW m_g0(R0), g + MOVW R0, g_m(g) + BL runtime·save_g(SB) + + // Layout new m scheduler stack on os stack. + MOVW R13, R0 + MOVW R0, g_stack+stack_hi(g) + SUB $(64*1024), R0 + MOVW R0, (g_stack+stack_lo)(g) + MOVW R0, g_stackguard0(g) + MOVW R0, g_stackguard1(g) + + BL runtime·emptyfunc(SB) // fault if stack check is wrong + BL runtime·mstart(SB) + + // Exit the thread. + MOVW $0, R0 + MOVM.IA.W (R13), [R4-R11, R15] // pop {r4-r11, pc} + +// Runs on OS stack. +// duration (in -100ns units) is in dt+0(FP). +// g may be nil. +TEXT runtime·usleep2(SB),NOSPLIT|NOFRAME,$0-4 + MOVW dt+0(FP), R3 + MOVM.DB.W [R4, R14], (R13) // push {r4, lr} + MOVW R13, R4 // Save SP + SUB $8, R13 // R13 = R13 - 8 + BIC $0x7, R13 // Align SP for ABI + MOVW $0, R1 // R1 = FALSE (alertable) + MOVW $-1, R0 // R0 = handle + MOVW R13, R2 // R2 = pTime + MOVW R3, 0(R2) // time_lo + MOVW R0, 4(R2) // time_hi + MOVW runtime·_NtWaitForSingleObject(SB), R3 + BL (R3) + MOVW R4, R13 // Restore SP + MOVM.IA.W (R13), [R4, R15] // pop {R4, pc} + +// Runs on OS stack. +TEXT runtime·switchtothread(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R14], (R13) // push {R4, lr} + MOVW R13, R4 + BIC $0x7, R13 // alignment for ABI + MOVW runtime·_SwitchToThread(SB), R0 + BL (R0) + MOVW R4, R13 // restore stack pointer + MOVM.IA.W (R13), [R4, R15] // pop {R4, pc} + +TEXT ·publicationBarrier(SB),NOSPLIT|NOFRAME,$0-0 + B runtime·armPublicationBarrier(SB) + +// never called (this is a GOARM=7 platform) +TEXT runtime·read_tls_fallback(SB),NOSPLIT,$0 + MOVW $0xabcd, R0 + MOVW R0, (R0) + RET + +TEXT runtime·nanotime1(SB),NOSPLIT,$0-8 + MOVW $0, R0 + MOVB runtime·useQPCTime(SB), R0 + CMP $0, R0 + BNE useQPC + MOVW $_INTERRUPT_TIME, R3 +loop: + MOVW time_hi1(R3), R1 + DMB MB_ISH + MOVW time_lo(R3), R0 + DMB MB_ISH + MOVW time_hi2(R3), R2 + CMP R1, R2 + BNE loop + + // wintime = R1:R0, multiply by 100 + MOVW $100, R2 + MULLU R0, R2, (R4, R3) // R4:R3 = R1:R0 * R2 + MULA R1, R2, R4, R4 + + // wintime*100 = R4:R3 + MOVW R3, ret_lo+0(FP) + MOVW R4, ret_hi+4(FP) + RET +useQPC: + RET runtime·nanotimeQPC(SB) // tail call + +// save_g saves the g register (R10) into thread local memory +// so that we can call externally compiled +// ARM code that will overwrite those registers. +// NOTE: runtime.gogo assumes that R1 is preserved by this function. +// runtime.mcall assumes this function only clobbers R0 and R11. +// Returns with g in R0. +// Save the value in the _TEB->TlsSlots array. +// Effectively implements TlsSetValue(). +// tls_g stores the TLS slot allocated TlsAlloc(). +TEXT runtime·save_g(SB),NOSPLIT,$0 + MRC 15, 0, R0, C13, C0, 2 + ADD $0xe10, R0 + MOVW $runtime·tls_g(SB), R11 + MOVW (R11), R11 + MOVW g, R11<<2(R0) + MOVW g, R0 // preserve R0 across call to setg<> + RET + +// load_g loads the g register from thread-local memory, +// for use after calling externally compiled +// ARM code that overwrote those registers. +// Get the value from the _TEB->TlsSlots array. +// Effectively implements TlsGetValue(). +TEXT runtime·load_g(SB),NOSPLIT,$0 + MRC 15, 0, R0, C13, C0, 2 + ADD $0xe10, R0 + MOVW $runtime·tls_g(SB), g + MOVW (g), g + MOVW g<<2(R0), g + RET + +// This is called from rt0_go, which runs on the system stack +// using the initial stack allocated by the OS. +// It calls back into standard C using the BL below. +// To do that, the stack pointer must be 8-byte-aligned. +TEXT runtime·_initcgo(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R14], (R13) // push {r4, lr} + + // Ensure stack is 8-byte aligned before calling C code + MOVW R13, R4 + BIC $0x7, R13 + + // Allocate a TLS slot to hold g across calls to external code + MOVW $runtime·_TlsAlloc(SB), R0 + MOVW (R0), R0 + BL (R0) + + // Assert that slot is less than 64 so we can use _TEB->TlsSlots + CMP $64, R0 + MOVW $runtime·abort(SB), R1 + BL.GE (R1) + + // Save Slot into tls_g + MOVW $runtime·tls_g(SB), R1 + MOVW R0, (R1) + + MOVW R4, R13 + MOVM.IA.W (R13), [R4, R15] // pop {r4, pc} + +// Holds the TLS Slot, which was allocated by TlsAlloc() +GLOBL runtime·tls_g+0(SB), NOPTR, $4 |