func balancedParentheses(s string) bool {
	var stack []byte
	for _, ch := range s {
		var open byte
		switch ch {
		case '(', '[', '{':
			stack = append(stack, byte(ch))
			continue
		case ')':
			open = '('
		case ']':
			open = '['
		case '}':
			open = '{'
		default:
			continue
		}
		// closing parenthesis/bracket must have matching opening
		top := len(stack) - 1
		if top < 0 || stack[top] != open {

				}
			}
			color[a] = black
		}

		if color[a] == grey {
			stack := []*Analyzer{a}
			inCycle := map[string]bool{}
			for len(stack) > 0 {
				current := stack[len(stack)-1]
				stack = stack[:len(stack)-1]
				if color[current] == grey && !inCycle[current.Name] {
					inCycle[current.Name] = true
					stack = append(stack, current.Requires...)
				}
			}

	gs.augmentName(st.Stack)

	// Handle the goroutine state transition.
	from, to := st.Goroutine()
	if from == to {
		// Filter out no-op events.
		return
	}
	if from.Executing() && !to.Executing() {
		if to == trace.GoWaiting {
			// Goroutine started blocking.
			gs.block(ev.Time(), ev.Stack(), st.Reason, ctx)
		} else {
			gs.stop(ev.Time(), ev.Stack(), ctx)
		}
	}

		return nil, fmt.Errorf("unexpected addr2line output: %s", resp)
	}

	var stack []plugin.Frame
	for {
		frame, end := d.readFrame()
		if end {
			break
		}

		if frame != (plugin.Frame{}) {
			stack = append(stack, frame)
		}
	}
	return stack, err
}

// addrInfo returns the stack frame information for a specific program

// license that can be found in the LICENSE file.

package sys

import (
	"internal/goarch"
	"internal/goos"
)

// AIX requires 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 + isRace

// DefaultPhysPageSize is the default physical page size.

//
//go:linkname checkptrBase
func checkptrBase(p unsafe.Pointer) uintptr {
	// stack
	if gp := getg(); gp.stack.lo <= uintptr(p) && uintptr(p) < gp.stack.hi {
		// TODO(mdempsky): Walk the stack to identify the
		// specific stack frame or even stack object that p
		// points into.
		//
		// In the mean time, use "1" as a pseudo-address to
		// represent the stack. This is an invalid address on
		// all platforms, so it's guaranteed to be distinct

			break
		}
	}
	return funcName
}

// Prune removes all nodes beneath a node matching dropRx, and not
// matching keepRx. If the root node of a Sample matches, the sample
// will have an empty stack.
func (p *Profile) Prune(dropRx, keepRx *regexp.Regexp) {
	prune := make(map[uint64]bool)
	pruneBeneath := make(map[uint64]bool)

	// simplifyFunc can be expensive, so cache results.

	}
	if spec.IsStack {
		len := int(args[1])
		for i := 0; i < len; i++ {
			line, err := r.nextLine()
			if err == io.EOF {
				return Event{}, fmt.Errorf("unexpected EOF while reading stack: args=%v", args)
			}
			if err != nil {
				return Event{}, err
			}
			frame, err := readArgs(line, frameFields)
			if err != nil {
				return Event{}, err
			}
			args = append(args, frame...)
		}
	}

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package net

import (
	"internal/testenv"
	"reflect"
	"testing"
)

// The full stack test cases for IPConn have been moved to the
// following:
//	golang.org/x/net/ipv4
//	golang.org/x/net/ipv6
//	golang.org/x/net/icmp

type resolveIPAddrTest struct {
	network       string
	litAddrOrName string

	TLSBSS = 256

	// Do not insert instructions to allocate a stack frame for this function.
	// Only valid on functions that declare a frame size of 0.
	// TODO(mwhudson): only implemented for ppc64x at present.
	NOFRAME = 512

	// Function can call reflect.Type.Method or reflect.Type.MethodByName.
	REFLECTMETHOD = 1024

	// Function is the outermost frame of the call stack. Call stack unwinders
	// should stop at this function.
	TOPFRAME = 2048