runtime: make windows exception handler code arch independent

Mainly it is simple copy. But I had to change amd64
lastcontinuehandler return value from uint32 to int32.
I don't remember how it happened to be uint32, but new
int32 is matching better with Windows documentation (LONG).
I don't think it matters one way or the others.

Change-Id: I6935224a2470ad6301e27590f2baa86c13bbe8d5
Reviewed-on: https://go-review.googlesource.com/8686
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/runtime/os1_windows_386.go

@@ -1,105 +0,0 @@
-// Copyright 2009 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.
-
-package runtime
-
-import (
-	"unsafe"
-)
-
-func isgoexception(info *exceptionrecord, r *context) bool {
-	// Only handle exception if executing instructions in Go binary
-	// (not Windows library code).
-	if r.ip() < themoduledata.text || themoduledata.etext < r.ip() {
-		return false
-	}
-
-	if issigpanic(info.exceptioncode) == 0 {
-		return false
-	}
-
-	return true
-}
-
-// Called by sigtramp from Windows VEH handler.
-// Return value signals whether the exception has been handled (EXCEPTION_CONTINUE_EXECUTION)
-// or should be made available to other handlers in the chain (EXCEPTION_CONTINUE_SEARCH).
-func exceptionhandler(info *exceptionrecord, r *context, gp *g) int32 {
-	if !isgoexception(info, r) {
-		return _EXCEPTION_CONTINUE_SEARCH
-	}
-
-	// Make it look like a call to the signal func.
-	// Have to pass arguments out of band since
-	// augmenting the stack frame would break
-	// the unwinding code.
-	gp.sig = info.exceptioncode
-	gp.sigcode0 = uintptr(info.exceptioninformation[0])
-	gp.sigcode1 = uintptr(info.exceptioninformation[1])
-	gp.sigpc = r.ip()
-
-	// Only push runtime·sigpanic if r.ip() != 0.
-	// If r.ip() == 0, probably panicked because of a
-	// call to a nil func.  Not pushing that onto sp will
-	// make the trace look like a call to runtime·sigpanic instead.
-	// (Otherwise the trace will end at runtime·sigpanic and we
-	// won't get to see who faulted.)
-	if r.ip() != 0 {
-		sp := unsafe.Pointer(r.sp())
-		sp = add(sp, ^uintptr(unsafe.Sizeof(uintptr(0))-1)) // sp--
-		*((*uintptr)(sp)) = r.ip()
-		r.setsp(uintptr(sp))
-	}
-	r.setip(funcPC(sigpanic))
-	return _EXCEPTION_CONTINUE_EXECUTION
-}
-
-var testingWER bool
-
-// lastcontinuehandler is reached, because runtime cannot handle
-// current exception. lastcontinuehandler will print crash info and exit.
-func lastcontinuehandler(info *exceptionrecord, r *context, gp *g) int32 {
-	if testingWER {
-		return _EXCEPTION_CONTINUE_SEARCH
-	}
-
-	_g_ := getg()
-
-	if panicking != 0 { // traceback already printed
-		exit(2)
-	}
-	panicking = 1
-
-	print("Exception ", hex(info.exceptioncode), " ", hex(info.exceptioninformation[0]), " ", hex(info.exceptioninformation[1]), " ", hex(r.ip()), "\n")
-
-	print("PC=", hex(r.ip()), "\n")
-	if _g_.m.lockedg != nil && _g_.m.ncgo > 0 && gp == _g_.m.g0 {
-		print("signal arrived during cgo execution\n")
-		gp = _g_.m.lockedg
-	}
-	print("\n")
-
-	var docrash bool
-	if gotraceback(&docrash) > 0 {
-		tracebacktrap(r.ip(), r.sp(), 0, gp)
-		tracebackothers(gp)
-		dumpregs(r)
-	}
-
-	if docrash {
-		crash()
-	}
-
-	exit(2)
-	return 0 // not reached
-}
-
-func sigenable(sig uint32) {
-}
-
-func sigdisable(sig uint32) {
-}
-
-func sigignore(sig uint32) {
-}

src/runtime/signal_windows.go

@@ -71,7 +71,7 @@ var testingWER bool
 
 // lastcontinuehandler is reached, because runtime cannot handle
 // current exception. lastcontinuehandler will print crash info and exit.
-func lastcontinuehandler(info *exceptionrecord, r *context, gp *g) uint32 {
+func lastcontinuehandler(info *exceptionrecord, r *context, gp *g) int32 {
 	if testingWER {
 		return _EXCEPTION_CONTINUE_SEARCH
 	}