//
// backtrack is a fast replacement for the NFA code on small
// regexps when onepass cannot be used.

package regexp

import (
	"regexp/syntax"
	"sync"
)

// A job is an entry on the backtracker's job stack. It holds
// the instruction pc and the position in the input.
type job struct {
	pc  uint32
	arg bool
	pos int
}

const (
	visitedBits        = 32
	maxBacktrackProg   = 500        // len(prog.Inst) <= max

func enableWER() {}

// winlibcall is not implemented on non-Windows systems,
// but it is used in non-OS-specific parts of the runtime.
// Define it as an empty struct to avoid wasting stack space.

	// we stored an integer in that pointer. That integer just happens
	// to be the address of i.
	// v is also the address of i.
	// p has a base type which is marked not-in-heap, so it
	// should not be adjusted when the stack is copied.
	recurse(100, p, v)
}
func recurse(n int, p *S, v uintptr) {
	if n > 0 {
		recurse(n-1, p, v)
	}
	if uintptr(unsafe.Pointer(p)) != v {
		panic("adjusted notinheap pointer")
	}

	F1 string
	F2 StructF0S1
}

type StructF0S1 struct {
	_ uint16
}

// 0 returns 3 params
//go:registerparams
//go:noinline
func Test0(p0 uint32, p1 StructF0S0, p2 int32) {
	// consume some stack space, so as to trigger morestack
	var pad [256]uint64
	pad[FailCount]++
	if p0 == 0 {
		return
	}
	p1f0c := int16(-3096)
	if p1.F0 != p1f0c {
		NoteFailureElem(0, "genChecker0", "parm", 1, 0, pad[0])
		return

		Parent: parent,
		Pos:    pos,
		Func:   func_,
		Name:   name,
	}
	tree.nodes = append(tree.nodes, call)
	return r
}

// AllParents invokes do on each InlinedCall in the inlining call
// stack, from outermost to innermost.
//
// That is, if inlIndex corresponds to f inlining g inlining h,
// AllParents invokes do with the call for inlining g into f, and then
// inlining h into g.

	Time      float64 `json:"ts"`
	Dur       float64 `json:"dur,omitempty"`
	PID       uint64  `json:"pid"`
	TID       uint64  `json:"tid"`
	ID        uint64  `json:"id,omitempty"`
	BindPoint string  `json:"bp,omitempty"`
	Stack     int     `json:"sf,omitempty"`
	EndStack  int     `json:"esf,omitempty"`
	Arg       any     `json:"args,omitempty"`
	Cname     string  `json:"cname,omitempty"`
	Category  string  `json:"cat,omitempty"`
}

}

// CheckPtrAlignmentNilPtr tests that checkptrAlignment doesn't crash
// on nil pointers (#47430).
func CheckPtrAlignmentNilPtr() {
	var do func(int)
	do = func(n int) {
		// Inflate the stack so runtime.shrinkstack gets called during GC
		if n > 0 {
			do(n - 1)
		}

		var p unsafe.Pointer
		_ = (*int)(p)
	}

	go func() {
		for {
			runtime.GC()
		}
	}()

	go func() {

}

// flush empties out unallocated free pages in the given cache
// into s. Then, it clears the cache, such that empty returns
// true.
//
// p.mheapLock must be held.
//
// Must run on the system stack because p.mheapLock must be held.
//
//go:systemstack
func (c *pageCache) flush(p *pageAlloc) {
	assertLockHeld(p.mheapLock)

	if c.empty() {
		return
	}
	ci := chunkIndex(c.base)

	}
	return i;
#else
	return 0;
#endif
}
*/
import "C"

import (
	"internal/testenv"
	"reflect"
	"runtime"
	"strings"
	"testing"
	"unsafe"
)

// Test that the stack can be unwound through a call out and call back
// into Go.
func testCallbackCallersSEH(t *testing.T) {
	testenv.SkipIfOptimizationOff(t) // This test requires inlining.
	if runtime.Compiler != "gc" {

	}
}

// filterStackRootFunc returns an event filter that returns true if the function
// at the root of the stack trace is named name.
func filterStackRootFunc(name string) eventFilterFn {
	return func(e *format.Event, data *format.Data) bool {
		frames := stackFrames(data, e.Stack)
		rootFrame := frames[len(frames)-1]
		return strings.HasPrefix(rootFrame, name+":")
	}
}