62 lines
1.7 KiB
Go
62 lines
1.7 KiB
Go
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// Copyright 2013 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package pointer
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// This file defines the internal (context-sensitive) call graph.
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import (
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"fmt"
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"go/token"
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"golang.org/x/tools/go/ssa"
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)
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type cgnode struct {
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fn *ssa.Function
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obj nodeid // start of this contour's object block
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sites []*callsite // ordered list of callsites within this function
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callersite *callsite // where called from, if known; nil for shared contours
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}
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// contour returns a description of this node's contour.
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func (n *cgnode) contour() string {
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if n.callersite == nil {
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return "shared contour"
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}
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if n.callersite.instr != nil {
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return fmt.Sprintf("as called from %s", n.callersite.instr.Parent())
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}
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return fmt.Sprintf("as called from intrinsic (targets=n%d)", n.callersite.targets)
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}
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func (n *cgnode) String() string {
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return fmt.Sprintf("cg%d:%s", n.obj, n.fn)
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}
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// A callsite represents a single call site within a cgnode;
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// it is implicitly context-sensitive.
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// callsites never represent calls to built-ins;
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// they are handled as intrinsics.
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//
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type callsite struct {
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targets nodeid // pts(·) contains objects for dynamically called functions
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instr ssa.CallInstruction // the call instruction; nil for synthetic/intrinsic
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}
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func (c *callsite) String() string {
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if c.instr != nil {
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return c.instr.Common().Description()
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}
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return "synthetic function call"
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}
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// pos returns the source position of this callsite, or token.NoPos if implicit.
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func (c *callsite) pos() token.Pos {
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if c.instr != nil {
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return c.instr.Pos()
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}
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return token.NoPos
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}
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