runtime: use compileCallback for ctrlhandler

This replaces the externalthreadhandler-based implementation of
ctrlhandler with one based on compileCallback. This is a step toward
eliminating externalthreadhandler.

For #45530.

Change-Id: I2de2f2f37777af292db67ccf8057b7566aab81f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/309632
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

6 files changed, 9 insertions, 34 deletions

diff --git a/src/cmd/link/internal/ld/pe.go b/src/cmd/link/internal/ld/pe.go
index b590d5082d..dc1b53010a 100644
--- a/src/cmd/link/internal/ld/pe.go
+++ b/src/cmd/link/internal/ld/pe.go
@@ -947,8 +947,8 @@ func (f *peFile) writeOptionalHeader(ctxt *Link) {
 	// calls that may need more stack than we think.
 	//
 	// The default stack reserve size directly affects only the main
-	// thread, ctrlhandler thread, and profileloop thread. For
-	// these, it must be greater than the stack size assumed by
+	// thread and threads that enter in externalthreadhandler.
+	// For this, it must be greater than the stack size assumed by
 	// externalthreadhandler.
 	//
 	// For other threads, the runtime explicitly asks the kernel
diff --git a/src/runtime/os_windows.go b/src/runtime/os_windows.go
index 705b42c61c..77ad075be1 100644
--- a/src/runtime/os_windows.go
+++ b/src/runtime/os_windows.go
@@ -149,9 +149,6 @@ var (
 // to start new os thread.
 func tstart_stdcall(newm *m)
 
-// Called by OS using stdcall ABI.
-func ctrlhandler()
-
 // Init-time helper
 func wintls()
 
@@ -557,8 +554,6 @@ func osinit() {
 
 	initExceptionHandler()
 
-	stdcall2(_SetConsoleCtrlHandler, funcPC(ctrlhandler), 1)
-
 	initHighResTimer()
 	timeBeginPeriodRetValue = osRelax(false)
 
@@ -685,8 +680,12 @@ func goenvs() {
 
 	stdcall1(_FreeEnvironmentStringsW, uintptr(strings))
 
-	// We call this all the way here, late in init, so that malloc works
-	// for the callback function this generates.
+	// We call these all the way here, late in init, so that malloc works
+	// for the callback functions these generate.
+	var fn interface{} = ctrlHandler
+	ctrlHandlerPC := compileCallback(*efaceOf(&fn), true)
+	stdcall2(_SetConsoleCtrlHandler, ctrlHandlerPC, 1)
+
 	monitorSuspendResume()
 }
 
@@ -1176,7 +1175,7 @@ func usleep(us uint32) {
 	})
 }
 
-func ctrlhandler1(_type uint32) uint32 {
+func ctrlHandler(_type uint32) uintptr {
 	var s uint32
 
 	switch _type {
diff --git a/src/runtime/sys_windows_386.s b/src/runtime/sys_windows_386.s
index be4268a9c0..b1c27c40d9 100644
--- a/src/runtime/sys_windows_386.s
+++ b/src/runtime/sys_windows_386.s
@@ -156,15 +156,6 @@ TEXT runtime·lastcontinuetramp<ABIInternal>(SB),NOSPLIT,$0-0
 	MOVL	$runtime·lastcontinuehandler(SB), AX
 	JMP	sigtramp<>(SB)
 
-// Called by OS using stdcall ABI: bool ctrlhandler(uint32).
-TEXT runtime·ctrlhandler<ABIInternal>(SB),NOSPLIT,$0
-	PUSHL	$runtime·ctrlhandler1(SB)
-	NOP	SP	// tell vet SP changed - stop checking offsets
-	CALL	runtime·externalthreadhandler<ABIInternal>(SB)
-	MOVL	4(SP), CX
-	ADDL	$12, SP
-	JMP	CX
-
 // Called by OS using stdcall ABI: uint32 profileloop(void*).
 TEXT runtime·profileloop<ABIInternal>(SB),NOSPLIT,$0
 	PUSHL	$runtime·profileloop1(SB)
diff --git a/src/runtime/sys_windows_amd64.s b/src/runtime/sys_windows_amd64.s
index 1fd8bf5c5c..e9428c36db 100644
--- a/src/runtime/sys_windows_amd64.s
+++ b/src/runtime/sys_windows_amd64.s
@@ -202,13 +202,6 @@ TEXT runtime·lastcontinuetramp<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-0
 	MOVQ	$runtime·lastcontinuehandler(SB), AX
 	JMP	sigtramp<>(SB)
 
-TEXT runtime·ctrlhandler<ABIInternal>(SB),NOSPLIT|NOFRAME,$8
-	MOVQ	CX, 16(SP)		// spill
-	MOVQ	$runtime·ctrlhandler1(SB), CX
-	MOVQ	CX, 0(SP)
-	CALL	runtime·externalthreadhandler<ABIInternal>(SB)
-	RET
-
 TEXT runtime·profileloop<ABIInternal>(SB),NOSPLIT|NOFRAME,$8
 	MOVQ	$runtime·profileloop1(SB), CX
 	MOVQ	CX, 0(SP)
diff --git a/src/runtime/sys_windows_arm.s b/src/runtime/sys_windows_arm.s
index 72de89dc84..304bba22e0 100644
--- a/src/runtime/sys_windows_arm.s
+++ b/src/runtime/sys_windows_arm.s
@@ -233,10 +233,6 @@ TEXT runtime·lastcontinuetramp<ABIInternal>(SB),NOSPLIT|NOFRAME,$0
 	MOVW	$runtime·lastcontinuehandler(SB), R1
 	B	sigtramp<>(SB)
 
-TEXT runtime·ctrlhandler<ABIInternal>(SB),NOSPLIT|NOFRAME,$0
-	MOVW	$runtime·ctrlhandler1(SB), R1
-	B	runtime·externalthreadhandler<ABIInternal>(SB)
-
 TEXT runtime·profileloop<ABIInternal>(SB),NOSPLIT|NOFRAME,$0
 	MOVW	$runtime·profileloop1(SB), R1
 	B	runtime·externalthreadhandler<ABIInternal>(SB)
diff --git a/src/runtime/sys_windows_arm64.s b/src/runtime/sys_windows_arm64.s
index f54c868b26..4512fbc8b0 100644
--- a/src/runtime/sys_windows_arm64.s
+++ b/src/runtime/sys_windows_arm64.s
@@ -299,10 +299,6 @@ TEXT runtime·lastcontinuetramp(SB),NOSPLIT|NOFRAME,$0
 	MOVD	$runtime·lastcontinuehandler<ABIInternal>(SB), R1
 	B	sigtramp<>(SB)
 
-TEXT runtime·ctrlhandler<ABIInternal>(SB),NOSPLIT|NOFRAME,$0
-	MOVD	$runtime·ctrlhandler1(SB), R1
-	B	runtime·externalthreadhandler<ABIInternal>(SB)
-
 TEXT runtime·profileloop<ABIInternal>(SB),NOSPLIT|NOFRAME,$0
 	MOVD	$runtime·profileloop1(SB), R1
 	B	runtime·externalthreadhandler<ABIInternal>(SB)