// 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
// convert to machine-dependent ops
func lower(f *Func) {
// repeat rewrites until we find no more rewrites
applyRewrite(f, f.Config.lowerBlock, f.Config.lowerValue)
}
// checkLower checks for unlowered opcodes and fails if we find one.
func checkLower(f *Func) {
// Needs to be a separate phase because it must run after both
// lowering and a subsequent dead code elimination (because lowering
// rules may leave dead generic ops behind).
for _, b := range f.Blocks {
for _, v := range b.Values {
if !opcodeTable[v.Op].generic {
continue // lowered
}
switch v.Op {
case OpSP, OpSB, OpInitMem, OpArg, OpPhi, OpVarDef, OpVarKill, OpVarLive, OpKeepAlive, OpSelect0, OpSelect1:
continue // ok not to lower
case OpGetG:
if f.Config.hasGReg {
// has hardware g register, regalloc takes care of it
continue // ok not to lower
}
}
s := "not lowered: " + v.String() + ", " + v.Op.String() + " " + v.Type.SimpleString()
for _, a := range v.Args {
s += " " + a.Type.SimpleString()
}
f.Fatalf("%s", s)
}
}
}