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// Copyright 2023 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 abi
const (
// StackNosplitBase is the base maximum number of bytes that a chain of
// NOSPLIT functions can use.
//
// This value must be multiplied by the stack guard multiplier, so do not
// use it directly. See runtime/stack.go:stackNosplit and
// cmd/internal/objabi/stack.go:StackNosplit.
StackNosplitBase = 800
// We have three different sequences for stack bounds checks, depending on
// whether the stack frame of a function is small, big, or huge.
// After a stack split check the SP is allowed to be StackSmall bytes below
// the stack guard.
//
// Functions that need frames <= StackSmall can perform the stack check
// using a single comparison directly between the stack guard and the SP
// because we ensure that StackSmall bytes of stack space are available
// beyond the stack guard.
StackSmall = 128
// Functions that need frames <= StackBig can assume that neither
// SP-framesize nor stackGuard-StackSmall will underflow, and thus use a
// more efficient check. In order to ensure this, StackBig must be <= the
// size of the unmapped space at zero.
StackBig = 4096
)
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