mirror of
https://github.com/superseriousbusiness/gotosocial
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[chore] Update gin to v1.9.0 (#1553)
This commit is contained in:
Daenney
GitHub
690
vendor/github.com/twitchyliquid64/golang-asm/obj/dwarf.go
generated
vendored
Normal file
690
vendor/github.com/twitchyliquid64/golang-asm/obj/dwarf.go
generated
vendored
Normal file
@ -0,0 +1,690 @@
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// Copyright 2019 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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// Writes dwarf information to object files.
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package obj
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import (
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"github.com/twitchyliquid64/golang-asm/dwarf"
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"github.com/twitchyliquid64/golang-asm/objabi"
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"github.com/twitchyliquid64/golang-asm/src"
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"fmt"
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"sort"
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"sync"
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)
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// Generate a sequence of opcodes that is as short as possible.
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// See section 6.2.5
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const (
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LINE_BASE = -4
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LINE_RANGE = 10
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PC_RANGE = (255 - OPCODE_BASE) / LINE_RANGE
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OPCODE_BASE = 11
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)
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// generateDebugLinesSymbol fills the debug lines symbol of a given function.
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//
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// It's worth noting that this function doesn't generate the full debug_lines
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// DWARF section, saving that for the linker. This function just generates the
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// state machine part of debug_lines. The full table is generated by the
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// linker. Also, we use the file numbers from the full package (not just the
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// function in question) when generating the state machine. We do this so we
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// don't have to do a fixup on the indices when writing the full section.
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func (ctxt *Link) generateDebugLinesSymbol(s, lines *LSym) {
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dctxt := dwCtxt{ctxt}
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// Emit a LNE_set_address extended opcode, so as to establish the
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// starting text address of this function.
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dctxt.AddUint8(lines, 0)
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dwarf.Uleb128put(dctxt, lines, 1+int64(ctxt.Arch.PtrSize))
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dctxt.AddUint8(lines, dwarf.DW_LNE_set_address)
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dctxt.AddAddress(lines, s, 0)
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// Set up the debug_lines state machine to the default values
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// we expect at the start of a new sequence.
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stmt := true
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line := int64(1)
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pc := s.Func.Text.Pc
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var lastpc int64 // last PC written to line table, not last PC in func
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name := ""
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prologue, wrotePrologue := false, false
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// Walk the progs, generating the DWARF table.
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for p := s.Func.Text; p != nil; p = p.Link {
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prologue = prologue || (p.Pos.Xlogue() == src.PosPrologueEnd)
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// If we're not at a real instruction, keep looping!
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if p.Pos.Line() == 0 || (p.Link != nil && p.Link.Pc == p.Pc) {
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continue
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}
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newStmt := p.Pos.IsStmt() != src.PosNotStmt
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newName, newLine := linkgetlineFromPos(ctxt, p.Pos)
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// Output debug info.
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wrote := false
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if name != newName {
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newFile := ctxt.PosTable.FileIndex(newName) + 1 // 1 indexing for the table.
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dctxt.AddUint8(lines, dwarf.DW_LNS_set_file)
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dwarf.Uleb128put(dctxt, lines, int64(newFile))
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name = newName
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wrote = true
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}
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if prologue && !wrotePrologue {
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dctxt.AddUint8(lines, uint8(dwarf.DW_LNS_set_prologue_end))
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wrotePrologue = true
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wrote = true
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}
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if stmt != newStmt {
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dctxt.AddUint8(lines, uint8(dwarf.DW_LNS_negate_stmt))
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stmt = newStmt
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wrote = true
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}
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if line != int64(newLine) || wrote {
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pcdelta := p.Pc - pc
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lastpc = p.Pc
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putpclcdelta(ctxt, dctxt, lines, uint64(pcdelta), int64(newLine)-line)
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line, pc = int64(newLine), p.Pc
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}
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}
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// Because these symbols will be concatenated together by the
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// linker, we need to reset the state machine that controls the
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// debug symbols. Do this using an end-of-sequence operator.
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//
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// Note: at one point in time, Delve did not support multiple end
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// sequence ops within a compilation unit (bug for this:
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// https://github.com/go-delve/delve/issues/1694), however the bug
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// has since been fixed (Oct 2019).
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//
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// Issue 38192: the DWARF standard specifies that when you issue
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// an end-sequence op, the PC value should be one past the last
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// text address in the translation unit, so apply a delta to the
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// text address before the end sequence op. If this isn't done,
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// GDB will assign a line number of zero the last row in the line
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// table, which we don't want.
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lastlen := uint64(s.Size - (lastpc - s.Func.Text.Pc))
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putpclcdelta(ctxt, dctxt, lines, lastlen, 0)
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dctxt.AddUint8(lines, 0) // start extended opcode
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dwarf.Uleb128put(dctxt, lines, 1)
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dctxt.AddUint8(lines, dwarf.DW_LNE_end_sequence)
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}
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func putpclcdelta(linkctxt *Link, dctxt dwCtxt, s *LSym, deltaPC uint64, deltaLC int64) {
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// Choose a special opcode that minimizes the number of bytes needed to
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// encode the remaining PC delta and LC delta.
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var opcode int64
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if deltaLC < LINE_BASE {
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if deltaPC >= PC_RANGE {
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opcode = OPCODE_BASE + (LINE_RANGE * PC_RANGE)
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} else {
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opcode = OPCODE_BASE + (LINE_RANGE * int64(deltaPC))
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}
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} else if deltaLC < LINE_BASE+LINE_RANGE {
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if deltaPC >= PC_RANGE {
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opcode = OPCODE_BASE + (deltaLC - LINE_BASE) + (LINE_RANGE * PC_RANGE)
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if opcode > 255 {
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opcode -= LINE_RANGE
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}
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} else {
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opcode = OPCODE_BASE + (deltaLC - LINE_BASE) + (LINE_RANGE * int64(deltaPC))
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}
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} else {
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if deltaPC <= PC_RANGE {
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opcode = OPCODE_BASE + (LINE_RANGE - 1) + (LINE_RANGE * int64(deltaPC))
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if opcode > 255 {
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opcode = 255
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}
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} else {
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// Use opcode 249 (pc+=23, lc+=5) or 255 (pc+=24, lc+=1).
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//
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// Let x=deltaPC-PC_RANGE. If we use opcode 255, x will be the remaining
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// deltaPC that we need to encode separately before emitting 255. If we
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// use opcode 249, we will need to encode x+1. If x+1 takes one more
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// byte to encode than x, then we use opcode 255.
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//
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// In all other cases x and x+1 take the same number of bytes to encode,
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// so we use opcode 249, which may save us a byte in encoding deltaLC,
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// for similar reasons.
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switch deltaPC - PC_RANGE {
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// PC_RANGE is the largest deltaPC we can encode in one byte, using
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// DW_LNS_const_add_pc.
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//
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// (1<<16)-1 is the largest deltaPC we can encode in three bytes, using
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// DW_LNS_fixed_advance_pc.
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//
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// (1<<(7n))-1 is the largest deltaPC we can encode in n+1 bytes for
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// n=1,3,4,5,..., using DW_LNS_advance_pc.
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case PC_RANGE, (1 << 7) - 1, (1 << 16) - 1, (1 << 21) - 1, (1 << 28) - 1,
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(1 << 35) - 1, (1 << 42) - 1, (1 << 49) - 1, (1 << 56) - 1, (1 << 63) - 1:
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opcode = 255
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default:
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opcode = OPCODE_BASE + LINE_RANGE*PC_RANGE - 1 // 249
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}
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}
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}
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if opcode < OPCODE_BASE || opcode > 255 {
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panic(fmt.Sprintf("produced invalid special opcode %d", opcode))
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}
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// Subtract from deltaPC and deltaLC the amounts that the opcode will add.
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deltaPC -= uint64((opcode - OPCODE_BASE) / LINE_RANGE)
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deltaLC -= (opcode-OPCODE_BASE)%LINE_RANGE + LINE_BASE
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// Encode deltaPC.
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if deltaPC != 0 {
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if deltaPC <= PC_RANGE {
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// Adjust the opcode so that we can use the 1-byte DW_LNS_const_add_pc
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// instruction.
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opcode -= LINE_RANGE * int64(PC_RANGE-deltaPC)
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if opcode < OPCODE_BASE {
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panic(fmt.Sprintf("produced invalid special opcode %d", opcode))
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}
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dctxt.AddUint8(s, dwarf.DW_LNS_const_add_pc)
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} else if (1<<14) <= deltaPC && deltaPC < (1<<16) {
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dctxt.AddUint8(s, dwarf.DW_LNS_fixed_advance_pc)
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dctxt.AddUint16(s, uint16(deltaPC))
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} else {
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dctxt.AddUint8(s, dwarf.DW_LNS_advance_pc)
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dwarf.Uleb128put(dctxt, s, int64(deltaPC))
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}
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}
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// Encode deltaLC.
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if deltaLC != 0 {
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dctxt.AddUint8(s, dwarf.DW_LNS_advance_line)
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dwarf.Sleb128put(dctxt, s, deltaLC)
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}
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// Output the special opcode.
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dctxt.AddUint8(s, uint8(opcode))
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}
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// implement dwarf.Context
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type dwCtxt struct{ *Link }
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func (c dwCtxt) PtrSize() int {
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return c.Arch.PtrSize
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}
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func (c dwCtxt) AddInt(s dwarf.Sym, size int, i int64) {
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ls := s.(*LSym)
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ls.WriteInt(c.Link, ls.Size, size, i)
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}
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func (c dwCtxt) AddUint16(s dwarf.Sym, i uint16) {
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c.AddInt(s, 2, int64(i))
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}
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func (c dwCtxt) AddUint8(s dwarf.Sym, i uint8) {
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b := []byte{byte(i)}
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c.AddBytes(s, b)
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}
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func (c dwCtxt) AddBytes(s dwarf.Sym, b []byte) {
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ls := s.(*LSym)
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ls.WriteBytes(c.Link, ls.Size, b)
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}
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func (c dwCtxt) AddString(s dwarf.Sym, v string) {
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ls := s.(*LSym)
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ls.WriteString(c.Link, ls.Size, len(v), v)
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ls.WriteInt(c.Link, ls.Size, 1, 0)
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}
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func (c dwCtxt) AddAddress(s dwarf.Sym, data interface{}, value int64) {
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ls := s.(*LSym)
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size := c.PtrSize()
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if data != nil {
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rsym := data.(*LSym)
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ls.WriteAddr(c.Link, ls.Size, size, rsym, value)
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} else {
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ls.WriteInt(c.Link, ls.Size, size, value)
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}
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}
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func (c dwCtxt) AddCURelativeAddress(s dwarf.Sym, data interface{}, value int64) {
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ls := s.(*LSym)
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rsym := data.(*LSym)
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ls.WriteCURelativeAddr(c.Link, ls.Size, rsym, value)
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}
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func (c dwCtxt) AddSectionOffset(s dwarf.Sym, size int, t interface{}, ofs int64) {
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panic("should be used only in the linker")
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}
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func (c dwCtxt) AddDWARFAddrSectionOffset(s dwarf.Sym, t interface{}, ofs int64) {
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size := 4
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if isDwarf64(c.Link) {
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size = 8
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}
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ls := s.(*LSym)
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rsym := t.(*LSym)
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ls.WriteAddr(c.Link, ls.Size, size, rsym, ofs)
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r := &ls.R[len(ls.R)-1]
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r.Type = objabi.R_DWARFSECREF
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}
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func (c dwCtxt) AddFileRef(s dwarf.Sym, f interface{}) {
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ls := s.(*LSym)
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rsym := f.(*LSym)
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fidx := c.Link.PosTable.FileIndex(rsym.Name)
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// Note the +1 here -- the value we're writing is going to be an
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// index into the DWARF line table file section, whose entries
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// are numbered starting at 1, not 0.
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ls.WriteInt(c.Link, ls.Size, 4, int64(fidx+1))
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}
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func (c dwCtxt) CurrentOffset(s dwarf.Sym) int64 {
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ls := s.(*LSym)
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return ls.Size
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}
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// Here "from" is a symbol corresponding to an inlined or concrete
|
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// function, "to" is the symbol for the corresponding abstract
|
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// function, and "dclIdx" is the index of the symbol of interest with
|
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// respect to the Dcl slice of the original pre-optimization version
|
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// of the inlined function.
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func (c dwCtxt) RecordDclReference(from dwarf.Sym, to dwarf.Sym, dclIdx int, inlIndex int) {
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ls := from.(*LSym)
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tls := to.(*LSym)
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ridx := len(ls.R) - 1
|
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c.Link.DwFixups.ReferenceChildDIE(ls, ridx, tls, dclIdx, inlIndex)
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}
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func (c dwCtxt) RecordChildDieOffsets(s dwarf.Sym, vars []*dwarf.Var, offsets []int32) {
|
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ls := s.(*LSym)
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c.Link.DwFixups.RegisterChildDIEOffsets(ls, vars, offsets)
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}
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func (c dwCtxt) Logf(format string, args ...interface{}) {
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c.Link.Logf(format, args...)
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}
|
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|
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func isDwarf64(ctxt *Link) bool {
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return ctxt.Headtype == objabi.Haix
|
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}
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|
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func (ctxt *Link) dwarfSym(s *LSym) (dwarfInfoSym, dwarfLocSym, dwarfRangesSym, dwarfAbsFnSym, dwarfDebugLines *LSym) {
|
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if s.Type != objabi.STEXT {
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ctxt.Diag("dwarfSym of non-TEXT %v", s)
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}
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if s.Func.dwarfInfoSym == nil {
|
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s.Func.dwarfInfoSym = &LSym{
|
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Type: objabi.SDWARFFCN,
|
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}
|
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if ctxt.Flag_locationlists {
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s.Func.dwarfLocSym = &LSym{
|
||||
Type: objabi.SDWARFLOC,
|
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}
|
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}
|
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s.Func.dwarfRangesSym = &LSym{
|
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Type: objabi.SDWARFRANGE,
|
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}
|
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s.Func.dwarfDebugLinesSym = &LSym{
|
||||
Type: objabi.SDWARFLINES,
|
||||
}
|
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if s.WasInlined() {
|
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s.Func.dwarfAbsFnSym = ctxt.DwFixups.AbsFuncDwarfSym(s)
|
||||
}
|
||||
}
|
||||
return s.Func.dwarfInfoSym, s.Func.dwarfLocSym, s.Func.dwarfRangesSym, s.Func.dwarfAbsFnSym, s.Func.dwarfDebugLinesSym
|
||||
}
|
||||
|
||||
func (s *LSym) Length(dwarfContext interface{}) int64 {
|
||||
return s.Size
|
||||
}
|
||||
|
||||
// fileSymbol returns a symbol corresponding to the source file of the
|
||||
// first instruction (prog) of the specified function. This will
|
||||
// presumably be the file in which the function is defined.
|
||||
func (ctxt *Link) fileSymbol(fn *LSym) *LSym {
|
||||
p := fn.Func.Text
|
||||
if p != nil {
|
||||
f, _ := linkgetlineFromPos(ctxt, p.Pos)
|
||||
fsym := ctxt.Lookup(f)
|
||||
return fsym
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// populateDWARF fills in the DWARF Debugging Information Entries for
|
||||
// TEXT symbol 's'. The various DWARF symbols must already have been
|
||||
// initialized in InitTextSym.
|
||||
func (ctxt *Link) populateDWARF(curfn interface{}, s *LSym, myimportpath string) {
|
||||
info, loc, ranges, absfunc, lines := ctxt.dwarfSym(s)
|
||||
if info.Size != 0 {
|
||||
ctxt.Diag("makeFuncDebugEntry double process %v", s)
|
||||
}
|
||||
var scopes []dwarf.Scope
|
||||
var inlcalls dwarf.InlCalls
|
||||
if ctxt.DebugInfo != nil {
|
||||
scopes, inlcalls = ctxt.DebugInfo(s, info, curfn)
|
||||
}
|
||||
var err error
|
||||
dwctxt := dwCtxt{ctxt}
|
||||
filesym := ctxt.fileSymbol(s)
|
||||
fnstate := &dwarf.FnState{
|
||||
Name: s.Name,
|
||||
Importpath: myimportpath,
|
||||
Info: info,
|
||||
Filesym: filesym,
|
||||
Loc: loc,
|
||||
Ranges: ranges,
|
||||
Absfn: absfunc,
|
||||
StartPC: s,
|
||||
Size: s.Size,
|
||||
External: !s.Static(),
|
||||
Scopes: scopes,
|
||||
InlCalls: inlcalls,
|
||||
UseBASEntries: ctxt.UseBASEntries,
|
||||
}
|
||||
if absfunc != nil {
|
||||
err = dwarf.PutAbstractFunc(dwctxt, fnstate)
|
||||
if err != nil {
|
||||
ctxt.Diag("emitting DWARF for %s failed: %v", s.Name, err)
|
||||
}
|
||||
err = dwarf.PutConcreteFunc(dwctxt, fnstate)
|
||||
} else {
|
||||
err = dwarf.PutDefaultFunc(dwctxt, fnstate)
|
||||
}
|
||||
if err != nil {
|
||||
ctxt.Diag("emitting DWARF for %s failed: %v", s.Name, err)
|
||||
}
|
||||
// Fill in the debug lines symbol.
|
||||
ctxt.generateDebugLinesSymbol(s, lines)
|
||||
}
|
||||
|
||||
// DwarfIntConst creates a link symbol for an integer constant with the
|
||||
// given name, type and value.
|
||||
func (ctxt *Link) DwarfIntConst(myimportpath, name, typename string, val int64) {
|
||||
if myimportpath == "" {
|
||||
return
|
||||
}
|
||||
s := ctxt.LookupInit(dwarf.ConstInfoPrefix+myimportpath, func(s *LSym) {
|
||||
s.Type = objabi.SDWARFCONST
|
||||
ctxt.Data = append(ctxt.Data, s)
|
||||
})
|
||||
dwarf.PutIntConst(dwCtxt{ctxt}, s, ctxt.Lookup(dwarf.InfoPrefix+typename), myimportpath+"."+name, val)
|
||||
}
|
||||
|
||||
func (ctxt *Link) DwarfAbstractFunc(curfn interface{}, s *LSym, myimportpath string) {
|
||||
absfn := ctxt.DwFixups.AbsFuncDwarfSym(s)
|
||||
if absfn.Size != 0 {
|
||||
ctxt.Diag("internal error: DwarfAbstractFunc double process %v", s)
|
||||
}
|
||||
if s.Func == nil {
|
||||
s.Func = new(FuncInfo)
|
||||
}
|
||||
scopes, _ := ctxt.DebugInfo(s, absfn, curfn)
|
||||
dwctxt := dwCtxt{ctxt}
|
||||
filesym := ctxt.fileSymbol(s)
|
||||
fnstate := dwarf.FnState{
|
||||
Name: s.Name,
|
||||
Importpath: myimportpath,
|
||||
Info: absfn,
|
||||
Filesym: filesym,
|
||||
Absfn: absfn,
|
||||
External: !s.Static(),
|
||||
Scopes: scopes,
|
||||
UseBASEntries: ctxt.UseBASEntries,
|
||||
}
|
||||
if err := dwarf.PutAbstractFunc(dwctxt, &fnstate); err != nil {
|
||||
ctxt.Diag("emitting DWARF for %s failed: %v", s.Name, err)
|
||||
}
|
||||
}
|
||||
|
||||
// This table is designed to aid in the creation of references between
|
||||
// DWARF subprogram DIEs.
|
||||
//
|
||||
// In most cases when one DWARF DIE has to refer to another DWARF DIE,
|
||||
// the target of the reference has an LSym, which makes it easy to use
|
||||
// the existing relocation mechanism. For DWARF inlined routine DIEs,
|
||||
// however, the subprogram DIE has to refer to a child
|
||||
// parameter/variable DIE of the abstract subprogram. This child DIE
|
||||
// doesn't have an LSym, and also of interest is the fact that when
|
||||
// DWARF generation is happening for inlined function F within caller
|
||||
// G, it's possible that DWARF generation hasn't happened yet for F,
|
||||
// so there is no way to know the offset of a child DIE within F's
|
||||
// abstract function. Making matters more complex, each inlined
|
||||
// instance of F may refer to a subset of the original F's variables
|
||||
// (depending on what happens with optimization, some vars may be
|
||||
// eliminated).
|
||||
//
|
||||
// The fixup table below helps overcome this hurdle. At the point
|
||||
// where a parameter/variable reference is made (via a call to
|
||||
// "ReferenceChildDIE"), a fixup record is generate that records
|
||||
// the relocation that is targeting that child variable. At a later
|
||||
// point when the abstract function DIE is emitted, there will be
|
||||
// a call to "RegisterChildDIEOffsets", at which point the offsets
|
||||
// needed to apply fixups are captured. Finally, once the parallel
|
||||
// portion of the compilation is done, fixups can actually be applied
|
||||
// during the "Finalize" method (this can't be done during the
|
||||
// parallel portion of the compile due to the possibility of data
|
||||
// races).
|
||||
//
|
||||
// This table is also used to record the "precursor" function node for
|
||||
// each function that is the target of an inline -- child DIE references
|
||||
// have to be made with respect to the original pre-optimization
|
||||
// version of the function (to allow for the fact that each inlined
|
||||
// body may be optimized differently).
|
||||
type DwarfFixupTable struct {
|
||||
ctxt *Link
|
||||
mu sync.Mutex
|
||||
symtab map[*LSym]int // maps abstract fn LSYM to index in svec
|
||||
svec []symFixups
|
||||
precursor map[*LSym]fnState // maps fn Lsym to precursor Node, absfn sym
|
||||
}
|
||||
|
||||
type symFixups struct {
|
||||
fixups []relFixup
|
||||
doffsets []declOffset
|
||||
inlIndex int32
|
||||
defseen bool
|
||||
}
|
||||
|
||||
type declOffset struct {
|
||||
// Index of variable within DCL list of pre-optimization function
|
||||
dclIdx int32
|
||||
// Offset of var's child DIE with respect to containing subprogram DIE
|
||||
offset int32
|
||||
}
|
||||
|
||||
type relFixup struct {
|
||||
refsym *LSym
|
||||
relidx int32
|
||||
dclidx int32
|
||||
}
|
||||
|
||||
type fnState struct {
|
||||
// precursor function (really *gc.Node)
|
||||
precursor interface{}
|
||||
// abstract function symbol
|
||||
absfn *LSym
|
||||
}
|
||||
|
||||
func NewDwarfFixupTable(ctxt *Link) *DwarfFixupTable {
|
||||
return &DwarfFixupTable{
|
||||
ctxt: ctxt,
|
||||
symtab: make(map[*LSym]int),
|
||||
precursor: make(map[*LSym]fnState),
|
||||
}
|
||||
}
|
||||
|
||||
func (ft *DwarfFixupTable) GetPrecursorFunc(s *LSym) interface{} {
|
||||
if fnstate, found := ft.precursor[s]; found {
|
||||
return fnstate.precursor
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (ft *DwarfFixupTable) SetPrecursorFunc(s *LSym, fn interface{}) {
|
||||
if _, found := ft.precursor[s]; found {
|
||||
ft.ctxt.Diag("internal error: DwarfFixupTable.SetPrecursorFunc double call on %v", s)
|
||||
}
|
||||
|
||||
// initialize abstract function symbol now. This is done here so
|
||||
// as to avoid data races later on during the parallel portion of
|
||||
// the back end.
|
||||
absfn := ft.ctxt.LookupDerived(s, dwarf.InfoPrefix+s.Name+dwarf.AbstractFuncSuffix)
|
||||
absfn.Set(AttrDuplicateOK, true)
|
||||
absfn.Type = objabi.SDWARFABSFCN
|
||||
ft.ctxt.Data = append(ft.ctxt.Data, absfn)
|
||||
|
||||
// In the case of "late" inlining (inlines that happen during
|
||||
// wrapper generation as opposed to the main inlining phase) it's
|
||||
// possible that we didn't cache the abstract function sym for the
|
||||
// text symbol -- do so now if needed. See issue 38068.
|
||||
if s.Func != nil && s.Func.dwarfAbsFnSym == nil {
|
||||
s.Func.dwarfAbsFnSym = absfn
|
||||
}
|
||||
|
||||
ft.precursor[s] = fnState{precursor: fn, absfn: absfn}
|
||||
}
|
||||
|
||||
// Make a note of a child DIE reference: relocation 'ridx' within symbol 's'
|
||||
// is targeting child 'c' of DIE with symbol 'tgt'.
|
||||
func (ft *DwarfFixupTable) ReferenceChildDIE(s *LSym, ridx int, tgt *LSym, dclidx int, inlIndex int) {
|
||||
// Protect against concurrent access if multiple backend workers
|
||||
ft.mu.Lock()
|
||||
defer ft.mu.Unlock()
|
||||
|
||||
// Create entry for symbol if not already present.
|
||||
idx, found := ft.symtab[tgt]
|
||||
if !found {
|
||||
ft.svec = append(ft.svec, symFixups{inlIndex: int32(inlIndex)})
|
||||
idx = len(ft.svec) - 1
|
||||
ft.symtab[tgt] = idx
|
||||
}
|
||||
|
||||
// Do we have child DIE offsets available? If so, then apply them,
|
||||
// otherwise create a fixup record.
|
||||
sf := &ft.svec[idx]
|
||||
if len(sf.doffsets) > 0 {
|
||||
found := false
|
||||
for _, do := range sf.doffsets {
|
||||
if do.dclIdx == int32(dclidx) {
|
||||
off := do.offset
|
||||
s.R[ridx].Add += int64(off)
|
||||
found = true
|
||||
break
|
||||
}
|
||||
}
|
||||
if !found {
|
||||
ft.ctxt.Diag("internal error: DwarfFixupTable.ReferenceChildDIE unable to locate child DIE offset for dclIdx=%d src=%v tgt=%v", dclidx, s, tgt)
|
||||
}
|
||||
} else {
|
||||
sf.fixups = append(sf.fixups, relFixup{s, int32(ridx), int32(dclidx)})
|
||||
}
|
||||
}
|
||||
|
||||
// Called once DWARF generation is complete for a given abstract function,
|
||||
// whose children might have been referenced via a call above. Stores
|
||||
// the offsets for any child DIEs (vars, params) so that they can be
|
||||
// consumed later in on DwarfFixupTable.Finalize, which applies any
|
||||
// outstanding fixups.
|
||||
func (ft *DwarfFixupTable) RegisterChildDIEOffsets(s *LSym, vars []*dwarf.Var, coffsets []int32) {
|
||||
// Length of these two slices should agree
|
||||
if len(vars) != len(coffsets) {
|
||||
ft.ctxt.Diag("internal error: RegisterChildDIEOffsets vars/offsets length mismatch")
|
||||
return
|
||||
}
|
||||
|
||||
// Generate the slice of declOffset's based in vars/coffsets
|
||||
doffsets := make([]declOffset, len(coffsets))
|
||||
for i := range coffsets {
|
||||
doffsets[i].dclIdx = vars[i].ChildIndex
|
||||
doffsets[i].offset = coffsets[i]
|
||||
}
|
||||
|
||||
ft.mu.Lock()
|
||||
defer ft.mu.Unlock()
|
||||
|
||||
// Store offsets for this symbol.
|
||||
idx, found := ft.symtab[s]
|
||||
if !found {
|
||||
sf := symFixups{inlIndex: -1, defseen: true, doffsets: doffsets}
|
||||
ft.svec = append(ft.svec, sf)
|
||||
ft.symtab[s] = len(ft.svec) - 1
|
||||
} else {
|
||||
sf := &ft.svec[idx]
|
||||
sf.doffsets = doffsets
|
||||
sf.defseen = true
|
||||
}
|
||||
}
|
||||
|
||||
func (ft *DwarfFixupTable) processFixups(slot int, s *LSym) {
|
||||
sf := &ft.svec[slot]
|
||||
for _, f := range sf.fixups {
|
||||
dfound := false
|
||||
for _, doffset := range sf.doffsets {
|
||||
if doffset.dclIdx == f.dclidx {
|
||||
f.refsym.R[f.relidx].Add += int64(doffset.offset)
|
||||
dfound = true
|
||||
break
|
||||
}
|
||||
}
|
||||
if !dfound {
|
||||
ft.ctxt.Diag("internal error: DwarfFixupTable has orphaned fixup on %v targeting %v relidx=%d dclidx=%d", f.refsym, s, f.relidx, f.dclidx)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// return the LSym corresponding to the 'abstract subprogram' DWARF
|
||||
// info entry for a function.
|
||||
func (ft *DwarfFixupTable) AbsFuncDwarfSym(fnsym *LSym) *LSym {
|
||||
// Protect against concurrent access if multiple backend workers
|
||||
ft.mu.Lock()
|
||||
defer ft.mu.Unlock()
|
||||
|
||||
if fnstate, found := ft.precursor[fnsym]; found {
|
||||
return fnstate.absfn
|
||||
}
|
||||
ft.ctxt.Diag("internal error: AbsFuncDwarfSym requested for %v, not seen during inlining", fnsym)
|
||||
return nil
|
||||
}
|
||||
|
||||
// Called after all functions have been compiled; the main job of this
|
||||
// function is to identify cases where there are outstanding fixups.
|
||||
// This scenario crops up when we have references to variables of an
|
||||
// inlined routine, but that routine is defined in some other package.
|
||||
// This helper walks through and locate these fixups, then invokes a
|
||||
// helper to create an abstract subprogram DIE for each one.
|
||||
func (ft *DwarfFixupTable) Finalize(myimportpath string, trace bool) {
|
||||
if trace {
|
||||
ft.ctxt.Logf("DwarfFixupTable.Finalize invoked for %s\n", myimportpath)
|
||||
}
|
||||
|
||||
// Collect up the keys from the precursor map, then sort the
|
||||
// resulting list (don't want to rely on map ordering here).
|
||||
fns := make([]*LSym, len(ft.precursor))
|
||||
idx := 0
|
||||
for fn := range ft.precursor {
|
||||
fns[idx] = fn
|
||||
idx++
|
||||
}
|
||||
sort.Sort(BySymName(fns))
|
||||
|
||||
// Should not be called during parallel portion of compilation.
|
||||
if ft.ctxt.InParallel {
|
||||
ft.ctxt.Diag("internal error: DwarfFixupTable.Finalize call during parallel backend")
|
||||
}
|
||||
|
||||
// Generate any missing abstract functions.
|
||||
for _, s := range fns {
|
||||
absfn := ft.AbsFuncDwarfSym(s)
|
||||
slot, found := ft.symtab[absfn]
|
||||
if !found || !ft.svec[slot].defseen {
|
||||
ft.ctxt.GenAbstractFunc(s)
|
||||
}
|
||||
}
|
||||
|
||||
// Apply fixups.
|
||||
for _, s := range fns {
|
||||
absfn := ft.AbsFuncDwarfSym(s)
|
||||
slot, found := ft.symtab[absfn]
|
||||
if !found {
|
||||
ft.ctxt.Diag("internal error: DwarfFixupTable.Finalize orphan abstract function for %v", s)
|
||||
} else {
|
||||
ft.processFixups(slot, s)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
type BySymName []*LSym
|
||||
|
||||
func (s BySymName) Len() int { return len(s) }
|
||||
func (s BySymName) Less(i, j int) bool { return s[i].Name < s[j].Name }
|
||||
func (s BySymName) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
|
||||
Reference in New Issue
Block a user