Skip to content
Permalink
4d5bb9c609
Switch branches/tags
Go to file
 
 
Cannot retrieve contributors at this time
374 lines (340 sloc) 11.1 KB
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package ssa
import (
"cmd/compile/internal/types"
"cmd/internal/obj"
"cmd/internal/objabi"
"cmd/internal/src"
)
// A Config holds readonly compilation information.
// It is created once, early during compilation,
// and shared across all compilations.
type Config struct {
arch string // "amd64", etc.
PtrSize int64 // 4 or 8; copy of cmd/internal/sys.Arch.PtrSize
RegSize int64 // 4 or 8; copy of cmd/internal/sys.Arch.RegSize
Types Types
lowerBlock blockRewriter // lowering function
lowerValue valueRewriter // lowering function
splitLoad valueRewriter // function for splitting merged load ops; only used on some architectures
registers []Register // machine registers
gpRegMask regMask // general purpose integer register mask
fpRegMask regMask // floating point register mask
fp32RegMask regMask // floating point register mask
fp64RegMask regMask // floating point register mask
specialRegMask regMask // special register mask
GCRegMap []*Register // garbage collector register map, by GC register index
FPReg int8 // register number of frame pointer, -1 if not used
LinkReg int8 // register number of link register if it is a general purpose register, -1 if not used
hasGReg bool // has hardware g register
ctxt *obj.Link // Generic arch information
optimize bool // Do optimization
noDuffDevice bool // Don't use Duff's device
useSSE bool // Use SSE for non-float operations
useAvg bool // Use optimizations that need Avg* operations
useHmul bool // Use optimizations that need Hmul* operations
use387 bool // GO386=387
SoftFloat bool //
Race bool // race detector enabled
NeedsFpScratch bool // No direct move between GP and FP register sets
BigEndian bool //
UseFMA bool // Use hardware FMA operation
}
type (
blockRewriter func(*Block) bool
valueRewriter func(*Value) bool
)
type Types struct {
Bool *types.Type
Int8 *types.Type
Int16 *types.Type
Int32 *types.Type
Int64 *types.Type
UInt8 *types.Type
UInt16 *types.Type
UInt32 *types.Type
UInt64 *types.Type
Int *types.Type
Float32 *types.Type
Float64 *types.Type
UInt *types.Type
Uintptr *types.Type
String *types.Type
BytePtr *types.Type // TODO: use unsafe.Pointer instead?
Int32Ptr *types.Type
UInt32Ptr *types.Type
IntPtr *types.Type
UintptrPtr *types.Type
Float32Ptr *types.Type
Float64Ptr *types.Type
BytePtrPtr *types.Type
}
// NewTypes creates and populates a Types.
func NewTypes() *Types {
t := new(Types)
t.SetTypPtrs()
return t
}
// SetTypPtrs populates t.
func (t *Types) SetTypPtrs() {
t.Bool = types.Types[types.TBOOL]
t.Int8 = types.Types[types.TINT8]
t.Int16 = types.Types[types.TINT16]
t.Int32 = types.Types[types.TINT32]
t.Int64 = types.Types[types.TINT64]
t.UInt8 = types.Types[types.TUINT8]
t.UInt16 = types.Types[types.TUINT16]
t.UInt32 = types.Types[types.TUINT32]
t.UInt64 = types.Types[types.TUINT64]
t.Int = types.Types[types.TINT]
t.Float32 = types.Types[types.TFLOAT32]
t.Float64 = types.Types[types.TFLOAT64]
t.UInt = types.Types[types.TUINT]
t.Uintptr = types.Types[types.TUINTPTR]
t.String = types.Types[types.TSTRING]
t.BytePtr = types.NewPtr(types.Types[types.TUINT8])
t.Int32Ptr = types.NewPtr(types.Types[types.TINT32])
t.UInt32Ptr = types.NewPtr(types.Types[types.TUINT32])
t.IntPtr = types.NewPtr(types.Types[types.TINT])
t.UintptrPtr = types.NewPtr(types.Types[types.TUINTPTR])
t.Float32Ptr = types.NewPtr(types.Types[types.TFLOAT32])
t.Float64Ptr = types.NewPtr(types.Types[types.TFLOAT64])
t.BytePtrPtr = types.NewPtr(types.NewPtr(types.Types[types.TUINT8]))
}
type Logger interface {
// Logf logs a message from the compiler.
Logf(string, ...interface{})
// Log reports whether logging is not a no-op
// some logging calls account for more than a few heap allocations.
Log() bool
// Fatal reports a compiler error and exits.
Fatalf(pos src.XPos, msg string, args ...interface{})
// Warnl writes compiler messages in the form expected by "errorcheck" tests
Warnl(pos src.XPos, fmt_ string, args ...interface{})
// Forwards the Debug flags from gc
Debug_checknil() bool
}
type Frontend interface {
CanSSA(t *types.Type) bool
Logger
// StringData returns a symbol pointing to the given string's contents.
StringData(string) interface{} // returns *gc.Sym
// Auto returns a Node for an auto variable of the given type.
// The SSA compiler uses this function to allocate space for spills.
Auto(src.XPos, *types.Type) GCNode
// Given the name for a compound type, returns the name we should use
// for the parts of that compound type.
SplitString(LocalSlot) (LocalSlot, LocalSlot)
SplitInterface(LocalSlot) (LocalSlot, LocalSlot)
SplitSlice(LocalSlot) (LocalSlot, LocalSlot, LocalSlot)
SplitComplex(LocalSlot) (LocalSlot, LocalSlot)
SplitStruct(LocalSlot, int) LocalSlot
SplitArray(LocalSlot) LocalSlot // array must be length 1
SplitInt64(LocalSlot) (LocalSlot, LocalSlot) // returns (hi, lo)
// DerefItab dereferences an itab function
// entry, given the symbol of the itab and
// the byte offset of the function pointer.
// It may return nil.
DerefItab(sym *obj.LSym, offset int64) *obj.LSym
// Line returns a string describing the given position.
Line(src.XPos) string
// AllocFrame assigns frame offsets to all live auto variables.
AllocFrame(f *Func)
// Syslook returns a symbol of the runtime function/variable with the
// given name.
Syslook(string) *obj.LSym
// UseWriteBarrier reports whether write barrier is enabled
UseWriteBarrier() bool
// SetWBPos indicates that a write barrier has been inserted
// in this function at position pos.
SetWBPos(pos src.XPos)
}
// interface used to hold a *gc.Node (a stack variable).
// We'd use *gc.Node directly but that would lead to an import cycle.
type GCNode interface {
Typ() *types.Type
String() string
IsSynthetic() bool
IsAutoTmp() bool
StorageClass() StorageClass
}
type StorageClass uint8
const (
ClassAuto StorageClass = iota // local stack variable
ClassParam // argument
ClassParamOut // return value
)
// NewConfig returns a new configuration object for the given architecture.
func NewConfig(arch string, types Types, ctxt *obj.Link, optimize bool) *Config {
c := &Config{arch: arch, Types: types}
c.useAvg = true
c.useHmul = true
switch arch {
case "amd64":
c.PtrSize = 8
c.RegSize = 8
c.lowerBlock = rewriteBlockAMD64
c.lowerValue = rewriteValueAMD64
c.splitLoad = rewriteValueAMD64splitload
c.registers = registersAMD64[:]
c.gpRegMask = gpRegMaskAMD64
c.fpRegMask = fpRegMaskAMD64
c.FPReg = framepointerRegAMD64
c.LinkReg = linkRegAMD64
c.hasGReg = false
case "386":
c.PtrSize = 4
c.RegSize = 4
c.lowerBlock = rewriteBlock386
c.lowerValue = rewriteValue386
c.splitLoad = rewriteValue386splitload
c.registers = registers386[:]
c.gpRegMask = gpRegMask386
c.fpRegMask = fpRegMask386
c.FPReg = framepointerReg386
c.LinkReg = linkReg386
c.hasGReg = false
case "arm":
c.PtrSize = 4
c.RegSize = 4
c.lowerBlock = rewriteBlockARM
c.lowerValue = rewriteValueARM
c.registers = registersARM[:]
c.gpRegMask = gpRegMaskARM
c.fpRegMask = fpRegMaskARM
c.FPReg = framepointerRegARM
c.LinkReg = linkRegARM
c.hasGReg = true
case "arm64":
c.PtrSize = 8
c.RegSize = 8
c.lowerBlock = rewriteBlockARM64
c.lowerValue = rewriteValueARM64
c.registers = registersARM64[:]
c.gpRegMask = gpRegMaskARM64
c.fpRegMask = fpRegMaskARM64
c.FPReg = framepointerRegARM64
c.LinkReg = linkRegARM64
c.hasGReg = true
c.noDuffDevice = objabi.GOOS == "darwin" // darwin linker cannot handle BR26 reloc with non-zero addend
case "ppc64":
c.BigEndian = true
fallthrough
case "ppc64le":
c.PtrSize = 8
c.RegSize = 8
c.lowerBlock = rewriteBlockPPC64
c.lowerValue = rewriteValuePPC64
c.registers = registersPPC64[:]
c.gpRegMask = gpRegMaskPPC64
c.fpRegMask = fpRegMaskPPC64
c.FPReg = framepointerRegPPC64
c.LinkReg = linkRegPPC64
c.noDuffDevice = true // TODO: Resolve PPC64 DuffDevice (has zero, but not copy)
c.hasGReg = true
case "mips64":
c.BigEndian = true
fallthrough
case "mips64le":
c.PtrSize = 8
c.RegSize = 8
c.lowerBlock = rewriteBlockMIPS64
c.lowerValue = rewriteValueMIPS64
c.registers = registersMIPS64[:]
c.gpRegMask = gpRegMaskMIPS64
c.fpRegMask = fpRegMaskMIPS64
c.specialRegMask = specialRegMaskMIPS64
c.FPReg = framepointerRegMIPS64
c.LinkReg = linkRegMIPS64
c.hasGReg = true
case "s390x":
c.PtrSize = 8
c.RegSize = 8
c.lowerBlock = rewriteBlockS390X
c.lowerValue = rewriteValueS390X
c.registers = registersS390X[:]
c.gpRegMask = gpRegMaskS390X
c.fpRegMask = fpRegMaskS390X
c.FPReg = framepointerRegS390X
c.LinkReg = linkRegS390X
c.hasGReg = true
c.noDuffDevice = true
c.BigEndian = true
case "mips":
c.BigEndian = true
fallthrough
case "mipsle":
c.PtrSize = 4
c.RegSize = 4
c.lowerBlock = rewriteBlockMIPS
c.lowerValue = rewriteValueMIPS
c.registers = registersMIPS[:]
c.gpRegMask = gpRegMaskMIPS
c.fpRegMask = fpRegMaskMIPS
c.specialRegMask = specialRegMaskMIPS
c.FPReg = framepointerRegMIPS
c.LinkReg = linkRegMIPS
c.hasGReg = true
c.noDuffDevice = true
case "wasm":
c.PtrSize = 8
c.RegSize = 8
c.lowerBlock = rewriteBlockWasm
c.lowerValue = rewriteValueWasm
c.registers = registersWasm[:]
c.gpRegMask = gpRegMaskWasm
c.fpRegMask = fpRegMaskWasm
c.fp32RegMask = fp32RegMaskWasm
c.fp64RegMask = fp64RegMaskWasm
c.FPReg = framepointerRegWasm
c.LinkReg = linkRegWasm
c.hasGReg = true
c.noDuffDevice = true
c.useAvg = false
c.useHmul = false
default:
ctxt.Diag("arch %s not implemented", arch)
}
c.ctxt = ctxt
c.optimize = optimize
c.useSSE = true
c.UseFMA = true
// On Plan 9, floating point operations are not allowed in note handler.
if objabi.GOOS == "plan9" {
// Don't use FMA on Plan 9
c.UseFMA = false
// Don't use Duff's device and SSE on Plan 9 AMD64.
if arch == "amd64" {
c.noDuffDevice = true
c.useSSE = false
}
}
if ctxt.Flag_shared {
// LoweredWB is secretly a CALL and CALLs on 386 in
// shared mode get rewritten by obj6.go to go through
// the GOT, which clobbers BX.
opcodeTable[Op386LoweredWB].reg.clobbers |= 1 << 3 // BX
}
// Create the GC register map index.
// TODO: This is only used for debug printing. Maybe export config.registers?
gcRegMapSize := int16(0)
for _, r := range c.registers {
if r.gcNum+1 > gcRegMapSize {
gcRegMapSize = r.gcNum + 1
}
}
c.GCRegMap = make([]*Register, gcRegMapSize)
for i, r := range c.registers {
if r.gcNum != -1 {
c.GCRegMap[r.gcNum] = &c.registers[i]
}
}
return c
}
func (c *Config) Set387(b bool) {
c.NeedsFpScratch = b
c.use387 = b
}
func (c *Config) Ctxt() *obj.Link { return c.ctxt }