diff options
Diffstat (limited to 'src/runtime/syscall_windows.go')
| -rw-r--r-- | src/runtime/syscall_windows.go | 36 |
1 files changed, 29 insertions, 7 deletions
diff --git a/src/runtime/syscall_windows.go b/src/runtime/syscall_windows.go index 21f2452b5a..add40bb0b3 100644 --- a/src/runtime/syscall_windows.go +++ b/src/runtime/syscall_windows.go @@ -5,6 +5,7 @@ package runtime import ( + "internal/abi" "runtime/internal/sys" "unsafe" ) @@ -109,14 +110,19 @@ func compileCallback(fn eface, cdecl bool) (code uintptr) { // 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. + // 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" && (k == kindFloat32 || k == kindFloat64) { + 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. + // currently spill. arm passes floating-point + // arguments in VFP registers, which we also + // don't support. panic("compileCallback: float arguments not supported") } @@ -128,6 +134,7 @@ func compileCallback(fn eface, cdecl bool) (code uintptr) { // 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 @@ -139,7 +146,7 @@ func compileCallback(fn eface, cdecl bool) (code uintptr) { abiMap = append(abiMap, part) } - // cdecl, stdcall, and fastcall pad arguments to word size. + // cdecl, stdcall, fastcall, and arm pad arguments to word size. src += sys.PtrSize // The Go ABI packs arguments. dst += t.size @@ -205,7 +212,18 @@ func compileCallback(fn eface, cdecl bool) (code uintptr) { type callbackArgs struct { index uintptr - args unsafe.Pointer // Arguments in stdcall/cdecl convention, with registers spilled + // 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 @@ -216,7 +234,7 @@ func callbackWrap(a *callbackArgs) { c := cbs.ctxt[a.index] a.retPop = c.retPop - // Convert from stdcall to Go ABI. + // Convert from C to Go ABI. var frame [callbackMaxFrame]byte goArgs := unsafe.Pointer(&frame) for _, part := range c.abiMap { @@ -225,7 +243,11 @@ func callbackWrap(a *callbackArgs) { // 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)) + // + // Pass a dummy RegArgs for now. + // TODO(mknyszek): Pass arguments in registers. + var regs abi.RegArgs + reflectcall(nil, unsafe.Pointer(c.fn), noescape(goArgs), uint32(c.retOffset)+sys.PtrSize, uint32(c.retOffset), uint32(c.retOffset)+sys.PtrSize, ®s) // Extract the result. a.result = *(*uintptr)(unsafe.Pointer(&frame[c.retOffset])) |