// 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 sys

import (

"internal/goarch"

"internal/goos"

)

// AIX and OpenBSD require a larger stack for syscalls.

// The race build also needs more stack. See issue 54291.

// This arithmetic must match that in cmd/internal/objabi/stack.go:stackGuardMultiplier.

const StackGuardMultiplier = 1 + goos.IsAix + goos.IsOpenbsd + isRace

// DefaultPhysPageSize is the default physical page size.

const DefaultPhysPageSize = goarch.DefaultPhysPageSize

// PCQuantum is the minimal unit for a program counter (1 on x86, 4 on most other systems).

// The various PC tables record PC deltas pre-divided by PCQuantum.

const PCQuantum = goarch.PCQuantum

// Int64Align is the required alignment for a 64-bit integer (4 on 32-bit systems, 8 on 64-bit).

const Int64Align = goarch.PtrSize

// MinFrameSize is the size of the system-reserved words at the bottom

// of a frame (just above the architectural stack pointer).

// It is zero on x86 and PtrSize on most non-x86 (LR-based) systems.

// On PowerPC it is larger, to cover three more reserved words:

// the compiler word, the link editor word, and the TOC save word.

const MinFrameSize = goarch.MinFrameSize

// StackAlign is the required alignment of the SP register.

// The stack must be at least word aligned, but some architectures require more.

const StackAlign = goarch.StackAlign