| // Copyright 2013 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. |
| |
| //go:build amd64 && (darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris) |
| |
| package runtime |
| |
| import ( |
| "internal/abi" |
| "internal/goarch" |
| "unsafe" |
| ) |
| |
| func dumpregs(c *sigctxt) { |
| print("rax ", hex(c.rax()), "\n") |
| print("rbx ", hex(c.rbx()), "\n") |
| print("rcx ", hex(c.rcx()), "\n") |
| print("rdx ", hex(c.rdx()), "\n") |
| print("rdi ", hex(c.rdi()), "\n") |
| print("rsi ", hex(c.rsi()), "\n") |
| print("rbp ", hex(c.rbp()), "\n") |
| print("rsp ", hex(c.rsp()), "\n") |
| print("r8 ", hex(c.r8()), "\n") |
| print("r9 ", hex(c.r9()), "\n") |
| print("r10 ", hex(c.r10()), "\n") |
| print("r11 ", hex(c.r11()), "\n") |
| print("r12 ", hex(c.r12()), "\n") |
| print("r13 ", hex(c.r13()), "\n") |
| print("r14 ", hex(c.r14()), "\n") |
| print("r15 ", hex(c.r15()), "\n") |
| print("rip ", hex(c.rip()), "\n") |
| print("rflags ", hex(c.rflags()), "\n") |
| print("cs ", hex(c.cs()), "\n") |
| print("fs ", hex(c.fs()), "\n") |
| print("gs ", hex(c.gs()), "\n") |
| } |
| |
| //go:nosplit |
| //go:nowritebarrierrec |
| func (c *sigctxt) sigpc() uintptr { return uintptr(c.rip()) } |
| |
| func (c *sigctxt) sigsp() uintptr { return uintptr(c.rsp()) } |
| func (c *sigctxt) siglr() uintptr { return 0 } |
| func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) } |
| |
| // preparePanic sets up the stack to look like a call to sigpanic. |
| func (c *sigctxt) preparePanic(sig uint32, gp *g) { |
| // Work around Leopard bug that doesn't set FPE_INTDIV. |
| // Look at instruction to see if it is a divide. |
| // Not necessary in Snow Leopard (si_code will be != 0). |
| if GOOS == "darwin" && sig == _SIGFPE && gp.sigcode0 == 0 { |
| pc := (*[4]byte)(unsafe.Pointer(gp.sigpc)) |
| i := 0 |
| if pc[i]&0xF0 == 0x40 { // 64-bit REX prefix |
| i++ |
| } else if pc[i] == 0x66 { // 16-bit instruction prefix |
| i++ |
| } |
| if pc[i] == 0xF6 || pc[i] == 0xF7 { |
| gp.sigcode0 = _FPE_INTDIV |
| } |
| } |
| |
| pc := uintptr(c.rip()) |
| sp := uintptr(c.rsp()) |
| |
| // In case we are panicking from external code, we need to initialize |
| // Go special registers. We inject sigpanic0 (instead of sigpanic), |
| // which takes care of that. |
| if shouldPushSigpanic(gp, pc, *(*uintptr)(unsafe.Pointer(sp))) { |
| c.pushCall(abi.FuncPCABI0(sigpanic0), pc) |
| } else { |
| // Not safe to push the call. Just clobber the frame. |
| c.set_rip(uint64(abi.FuncPCABI0(sigpanic0))) |
| } |
| } |
| |
| func (c *sigctxt) pushCall(targetPC, resumePC uintptr) { |
| // Make it look like we called target at resumePC. |
| sp := uintptr(c.rsp()) |
| sp -= goarch.PtrSize |
| *(*uintptr)(unsafe.Pointer(sp)) = resumePC |
| c.set_rsp(uint64(sp)) |
| c.set_rip(uint64(targetPC)) |
| } |