//	GoVersion(!go1.22) = ""
//
// GoVersion assumes that any tag or negated tag may independently be true,
// so that its analysis can be purely structural, without SAT solving.
// “Impossible” subexpressions may therefore affect the result.
//
// For example:
//
//	GoVersion((linux && !linux && go1.20) || go1.21) = "go1.20"
func GoVersion(x Expr) string {
	v := minVersion(x, +1)
	if v < 0 {
		return ""
	}

	{`a{1}`, `a`},
	{`a{2}`, `aa`},
	{`a{5}`, `aaaaa`},
	{`a{0,1}`, `a?`},
	// The next three are illegible because Simplify inserts (?:)
	// parens instead of () parens to avoid creating extra
	// captured subexpressions. The comments show a version with fewer parens.
	{`(a){0,2}`, `(?:(a)(a)?)?`},                       //       (aa?)?
	{`(a){0,4}`, `(?:(a)(?:(a)(?:(a)(a)?)?)?)?`},       //   (a(a(aa?)?)?)?

			if efmt != prev {
				pass.ReportRangef(e, "suspect %s: %s %s %s", op.name, efmt, op.tok, prev)
			}
		} else {
			seen[xfmt] = efmt
		}
	}
}

// split returns a slice of all subexpressions in e that are connected by op.
// For example, given 'a || (b || c) || d' with the or op,
// split returns []{d, c, b, a}.
// seen[e] is already true; any newly processed exprs are added to seen.

//
// The blocks of the CFG contain all the function's non-control
// statements.  The CFG does not contain control statements such as If,
// Switch, Select, and Branch, but does contain their subexpressions;
// also, each block records the control statement (Block.Stmt) that
// gave rise to it and its relationship (Block.Kind) to that statement.
//
// For example, this source code:
//
//	if x := f(); x != nil {

NOTE	null subexpression matches : 2002-06-06

E	(a*)*		a		(0,1)(0,1)
E	SAME		x		(0,0)(0,0)
E	SAME		aaaaaa		(0,6)(0,6)
E	SAME		aaaaaax		(0,6)(0,6)
E	(a*)+		a		(0,1)(0,1)
E	SAME		x		(0,0)(0,0)
E	SAME		aaaaaa		(0,6)(0,6)
E	SAME		aaaaaax		(0,6)(0,6)
E	(a+)*		a		(0,1)(0,1)
E	SAME		x		(0,0)
E	SAME		aaaaaa		(0,6)(0,6)
E	SAME		aaaaaax		(0,6)(0,6)
E	(a+)+		a		(0,1)(0,1)
E	SAME		x		NOMATCH
E	SAME		aaaaaa		(0,6)(0,6)

}

func (e *PrimaryTerm) aggregateRow(r Record, tableAlias string) error {
	switch {
	case e.ListExpr != nil:
		return e.ListExpr.aggregateRow(r, tableAlias)
	case e.SubExpression != nil:
		return e.SubExpression.aggregateRow(r, tableAlias)
	case e.FuncCall != nil:
		return e.FuncCall.aggregateRow(r, tableAlias)
	}
	return nil
}

func (e *FuncExpr) aggregateRow(r Record, tableAlias string) error {

				result = qProp{err: errInvalidKeypath}
				return
			}
		}
		result = qProp{isRowFunc: true}

	case e.ListExpr != nil:
		result = e.ListExpr.analyze(s)

	case e.SubExpression != nil:
		result = e.SubExpression.analyze(s)

	case e.FuncCall != nil:
		result = e.FuncCall.analyze(s)

	default:
		result = qProp{err: errUnexpectedInvalidNode}
	}
	return
}

	// regexp functions which contains 'Submatch' in their names will be 3.
	// Submatch 0 is the match of the entire expression, submatch 1 is
	// the match of the first parenthesized subexpression, and so on.
	// e.g.:
	// result := bootstraputil.BootstrapTokenRegexp.FindStringSubmatch("abcdef.1234567890123456")
	// result == []string{"abcdef.1234567890123456","abcdef","1234567890123456"}
	// len(result) == 3

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

package ssa

import (
	"cmd/compile/internal/types"
	"cmd/internal/src"
	"fmt"
	"sort"
)

// cse does common-subexpression elimination on the Function.
// Values are just relinked, nothing is deleted. A subsequent deadcode
// pass is required to actually remove duplicate expressions.
func cse(f *Func) {