From 73df946d56c74384511a194dd01dbe099584fd1a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 15:14:23 +0200 Subject: Adding upstream version 1.16.10. Signed-off-by: Daniel Baumann --- src/runtime/syscall_windows.go | 397 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 397 insertions(+) create mode 100644 src/runtime/syscall_windows.go (limited to 'src/runtime/syscall_windows.go') diff --git a/src/runtime/syscall_windows.go b/src/runtime/syscall_windows.go new file mode 100644 index 0000000..7835b49 --- /dev/null +++ b/src/runtime/syscall_windows.go @@ -0,0 +1,397 @@ +// Copyright 2014 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 ( + "runtime/internal/sys" + "unsafe" +) + +// cbs stores all registered Go callbacks. +var cbs struct { + lock mutex + ctxt [cb_max]winCallback + index map[winCallbackKey]int + n int +} + +// winCallback records information about a registered Go callback. +type winCallback struct { + fn *funcval // Go function + retPop uintptr // For 386 cdecl, how many bytes to pop on return + + // abiMap specifies how to translate from a C frame to a Go + // frame. This does not specify how to translate back because + // the result is always a uintptr. If the C ABI is fastcall, + // this assumes the four fastcall registers were first spilled + // to the shadow space. + abiMap []abiPart + // retOffset is the offset of the uintptr-sized result in the Go + // frame. + retOffset uintptr +} + +// abiPart encodes a step in translating between calling ABIs. +type abiPart struct { + src, dst uintptr + len uintptr +} + +func (a *abiPart) tryMerge(b abiPart) bool { + if a.src+a.len == b.src && a.dst+a.len == b.dst { + a.len += b.len + return true + } + return false +} + +type winCallbackKey struct { + fn *funcval + cdecl bool +} + +func callbackasm() + +// callbackasmAddr returns address of runtime.callbackasm +// function adjusted by i. +// On x86 and amd64, runtime.callbackasm is a series of CALL instructions, +// and we want callback to arrive at +// correspondent call instruction instead of start of +// runtime.callbackasm. +// On ARM, runtime.callbackasm is a series of mov and branch instructions. +// R12 is loaded with the callback index. Each entry is two instructions, +// hence 8 bytes. +func callbackasmAddr(i int) uintptr { + var entrySize int + switch GOARCH { + default: + panic("unsupported architecture") + case "386", "amd64": + entrySize = 5 + case "arm": + // On ARM, each entry is a MOV instruction + // followed by a branch instruction + entrySize = 8 + } + return funcPC(callbackasm) + uintptr(i*entrySize) +} + +const callbackMaxFrame = 64 * sys.PtrSize + +// compileCallback converts a Go function fn into a C function pointer +// that can be passed to Windows APIs. +// +// On 386, if cdecl is true, the returned C function will use the +// cdecl calling convention; otherwise, it will use stdcall. On amd64, +// it always uses fastcall. On arm, it always uses the ARM convention. +// +//go:linkname compileCallback syscall.compileCallback +func compileCallback(fn eface, cdecl bool) (code uintptr) { + if GOARCH != "386" { + // cdecl is only meaningful on 386. + cdecl = false + } + + if fn._type == nil || (fn._type.kind&kindMask) != kindFunc { + panic("compileCallback: expected function with one uintptr-sized result") + } + ft := (*functype)(unsafe.Pointer(fn._type)) + + // Check arguments and construct ABI translation. + var abiMap []abiPart + var src, dst uintptr + for _, t := range ft.in() { + if t.size > sys.PtrSize { + // We don't support this right now. In + // stdcall/cdecl, 64-bit ints and doubles are + // passed as two words (little endian); and + // structs are pushed on the stack. In + // fastcall, arguments larger than the word + // size are passed by reference. On arm, + // 8-byte aligned arguments round up to the + // next even register and can be split across + // registers and the stack. + panic("compileCallback: argument size is larger than uintptr") + } + if k := t.kind & kindMask; (GOARCH == "amd64" || GOARCH == "arm") && (k == kindFloat32 || k == kindFloat64) { + // In fastcall, floating-point arguments in + // the first four positions are passed in + // floating-point registers, which we don't + // currently spill. arm passes floating-point + // arguments in VFP registers, which we also + // don't support. + panic("compileCallback: float arguments not supported") + } + + // The Go ABI aligns arguments. + dst = alignUp(dst, uintptr(t.align)) + // In the C ABI, we're already on a word boundary. + // Also, sub-word-sized fastcall register arguments + // are stored to the least-significant bytes of the + // argument word and all supported Windows + // architectures are little endian, so src is already + // pointing to the right place for smaller arguments. + // The same is true on arm. + + // Copy just the size of the argument. Note that this + // could be a small by-value struct, but C and Go + // struct layouts are compatible, so we can copy these + // directly, too. + part := abiPart{src, dst, t.size} + // Add this step to the adapter. + if len(abiMap) == 0 || !abiMap[len(abiMap)-1].tryMerge(part) { + abiMap = append(abiMap, part) + } + + // cdecl, stdcall, fastcall, and arm pad arguments to word size. + src += sys.PtrSize + // The Go ABI packs arguments. + dst += t.size + } + // The Go ABI aligns the result to the word size. src is + // already aligned. + dst = alignUp(dst, sys.PtrSize) + retOffset := dst + + if len(ft.out()) != 1 { + panic("compileCallback: expected function with one uintptr-sized result") + } + if ft.out()[0].size != sys.PtrSize { + panic("compileCallback: expected function with one uintptr-sized result") + } + if k := ft.out()[0].kind & kindMask; k == kindFloat32 || k == kindFloat64 { + // In cdecl and stdcall, float results are returned in + // ST(0). In fastcall, they're returned in XMM0. + // Either way, it's not AX. + panic("compileCallback: float results not supported") + } + // Make room for the uintptr-sized result. + dst += sys.PtrSize + + if dst > callbackMaxFrame { + panic("compileCallback: function argument frame too large") + } + + // For cdecl, the callee is responsible for popping its + // arguments from the C stack. + var retPop uintptr + if cdecl { + retPop = src + } + + key := winCallbackKey{(*funcval)(fn.data), cdecl} + + lock(&cbs.lock) // We don't unlock this in a defer because this is used from the system stack. + + // Check if this callback is already registered. + if n, ok := cbs.index[key]; ok { + unlock(&cbs.lock) + return callbackasmAddr(n) + } + + // Register the callback. + if cbs.index == nil { + cbs.index = make(map[winCallbackKey]int) + } + n := cbs.n + if n >= len(cbs.ctxt) { + unlock(&cbs.lock) + throw("too many callback functions") + } + c := winCallback{key.fn, retPop, abiMap, retOffset} + cbs.ctxt[n] = c + cbs.index[key] = n + cbs.n++ + + unlock(&cbs.lock) + return callbackasmAddr(n) +} + +type callbackArgs struct { + index uintptr + // args points to the argument block. + // + // For cdecl and stdcall, all arguments are on the stack. + // + // For fastcall, the trampoline spills register arguments to + // the reserved spill slots below the stack arguments, + // resulting in a layout equivalent to stdcall. + // + // For arm, the trampoline stores the register arguments just + // below the stack arguments, so again we can treat it as one + // big stack arguments frame. + args unsafe.Pointer + // Below are out-args from callbackWrap + result uintptr + retPop uintptr // For 386 cdecl, how many bytes to pop on return +} + +// callbackWrap is called by callbackasm to invoke a registered C callback. +func callbackWrap(a *callbackArgs) { + c := cbs.ctxt[a.index] + a.retPop = c.retPop + + // Convert from C to Go ABI. + var frame [callbackMaxFrame]byte + goArgs := unsafe.Pointer(&frame) + for _, part := range c.abiMap { + memmove(add(goArgs, part.dst), add(a.args, part.src), part.len) + } + + // Even though this is copying back results, we can pass a nil + // type because those results must not require write barriers. + reflectcall(nil, unsafe.Pointer(c.fn), noescape(goArgs), uint32(c.retOffset)+sys.PtrSize, uint32(c.retOffset)) + + // Extract the result. + a.result = *(*uintptr)(unsafe.Pointer(&frame[c.retOffset])) +} + +const _LOAD_LIBRARY_SEARCH_SYSTEM32 = 0x00000800 + +// When available, this function will use LoadLibraryEx with the filename +// parameter and the important SEARCH_SYSTEM32 argument. But on systems that +// do not have that option, absoluteFilepath should contain a fallback +// to the full path inside of system32 for use with vanilla LoadLibrary. +//go:linkname syscall_loadsystemlibrary syscall.loadsystemlibrary +//go:nosplit +func syscall_loadsystemlibrary(filename *uint16, absoluteFilepath *uint16) (handle, err uintptr) { + lockOSThread() + c := &getg().m.syscall + + if useLoadLibraryEx { + c.fn = getLoadLibraryEx() + c.n = 3 + args := struct { + lpFileName *uint16 + hFile uintptr // always 0 + flags uint32 + }{filename, 0, _LOAD_LIBRARY_SEARCH_SYSTEM32} + c.args = uintptr(noescape(unsafe.Pointer(&args))) + } else { + c.fn = getLoadLibrary() + c.n = 1 + c.args = uintptr(noescape(unsafe.Pointer(&absoluteFilepath))) + } + + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + handle = c.r1 + if handle == 0 { + err = c.err + } + unlockOSThread() // not defer'd after the lockOSThread above to save stack frame size. + return +} + +//go:linkname syscall_loadlibrary syscall.loadlibrary +//go:nosplit +func syscall_loadlibrary(filename *uint16) (handle, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = getLoadLibrary() + c.n = 1 + c.args = uintptr(noescape(unsafe.Pointer(&filename))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + handle = c.r1 + if handle == 0 { + err = c.err + } + return +} + +//go:linkname syscall_getprocaddress syscall.getprocaddress +//go:nosplit +func syscall_getprocaddress(handle uintptr, procname *byte) (outhandle, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = getGetProcAddress() + c.n = 2 + c.args = uintptr(noescape(unsafe.Pointer(&handle))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + outhandle = c.r1 + if outhandle == 0 { + err = c.err + } + return +} + +//go:linkname syscall_Syscall syscall.Syscall +//go:nosplit +func syscall_Syscall(fn, nargs, a1, a2, a3 uintptr) (r1, r2, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = fn + c.n = nargs + c.args = uintptr(noescape(unsafe.Pointer(&a1))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + return c.r1, c.r2, c.err +} + +//go:linkname syscall_Syscall6 syscall.Syscall6 +//go:nosplit +func syscall_Syscall6(fn, nargs, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = fn + c.n = nargs + c.args = uintptr(noescape(unsafe.Pointer(&a1))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + return c.r1, c.r2, c.err +} + +//go:linkname syscall_Syscall9 syscall.Syscall9 +//go:nosplit +func syscall_Syscall9(fn, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = fn + c.n = nargs + c.args = uintptr(noescape(unsafe.Pointer(&a1))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + return c.r1, c.r2, c.err +} + +//go:linkname syscall_Syscall12 syscall.Syscall12 +//go:nosplit +func syscall_Syscall12(fn, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12 uintptr) (r1, r2, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = fn + c.n = nargs + c.args = uintptr(noescape(unsafe.Pointer(&a1))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + return c.r1, c.r2, c.err +} + +//go:linkname syscall_Syscall15 syscall.Syscall15 +//go:nosplit +func syscall_Syscall15(fn, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15 uintptr) (r1, r2, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = fn + c.n = nargs + c.args = uintptr(noescape(unsafe.Pointer(&a1))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + return c.r1, c.r2, c.err +} + +//go:linkname syscall_Syscall18 syscall.Syscall18 +//go:nosplit +func syscall_Syscall18(fn, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18 uintptr) (r1, r2, err uintptr) { + lockOSThread() + defer unlockOSThread() + c := &getg().m.syscall + c.fn = fn + c.n = nargs + c.args = uintptr(noescape(unsafe.Pointer(&a1))) + cgocall(asmstdcallAddr, unsafe.Pointer(c)) + return c.r1, c.r2, c.err +} -- cgit v1.2.3