Golang cmd-compile-internal-ssa.Type类(方法)实例源码

// moveByType returns the reg->reg move instruction of the given type.
func moveByType(t ssa.Type) obj.As {
	if t.IsFloat() {
		return s390x.AFMOVD
	} else {
		switch t.Size() {
		case 1:
			if t.IsSigned() {
				return s390x.AMOVB
			} else {
				return s390x.AMOVBZ
			}
		case 2:
			if t.IsSigned() {
				return s390x.AMOVH
			} else {
				return s390x.AMOVHZ
			}
		case 4:
			if t.IsSigned() {
				return s390x.AMOVW
			} else {
				return s390x.AMOVWZ
			}
		case 8:
			return s390x.AMOVD
		}
	}
	panic("bad load type")
}

// loadByType returns the load instruction of the given type.
func loadByType(t ssa.Type) obj.As {
	if t.IsFloat() {
		switch t.Size() {
		case 4:
			return arm.AMOVF
		case 8:
			return arm.AMOVD
		}
	} else {
		switch t.Size() {
		case 1:
			if t.IsSigned() {
				return arm.AMOVB
			} else {
				return arm.AMOVBU
			}
		case 2:
			if t.IsSigned() {
				return arm.AMOVH
			} else {
				return arm.AMOVHU
			}
		case 4:
			return arm.AMOVW
		}
	}
	panic("bad load type")
}

// storeByType returns the store instruction of the given type.
func storeByType(t ssa.Type, r int16) obj.As {
	if isFPreg(r) {
		if t.Size() == 4 { // float32 or int32
			return mips.AMOVF
		} else { // float64 or int64
			return mips.AMOVD
		}
	} else {
		switch t.Size() {
		case 1:
			return mips.AMOVB
		case 2:
			return mips.AMOVH
		case 4:
			return mips.AMOVW
		}
	}
	panic("bad store type")
}

// storeByType returns the store instruction of the given type.
func storeByType(t ssa.Type) obj.As {
	width := t.Size()
	if t.IsFloat() {
		switch width {
		case 4:
			return x86.AMOVSS
		case 8:
			return x86.AMOVSD
		}
	} else {
		switch width {
		case 1:
			return x86.AMOVB
		case 2:
			return x86.AMOVW
		case 4:
			return x86.AMOVL
		}
	}
	panic("bad store type")
}

// moveByType returns the reg->reg move instruction of the given type.
func moveByType(t ssa.Type) obj.As {
	if t.IsFloat() {
		// Moving the whole sse2 register is faster
		// than moving just the correct low portion of it.
		// There is no xmm->xmm move with 1 byte opcode,
		// so use movups, which has 2 byte opcode.
		return x86.AMOVUPS
	} else {
		switch t.Size() {
		case 1:
			// Avoids partial register write
			return x86.AMOVL
		case 2:
			return x86.AMOVL
		case 4:
			return x86.AMOVL
		case 8:
			return x86.AMOVQ
		case 16:
			return x86.AMOVUPS // int128s are in SSE registers
		default:
			panic(fmt.Sprintf("bad int register width %d:%s", t.Size(), t))
		}
	}
	panic("bad register type")
}

// moveByType returns the reg->reg move instruction of the given type.
func moveByType(t ssa.Type) obj.As {
	if t.IsFloat() {
		switch t.Size() {
		case 4:
			return x86.AMOVSS
		case 8:
			return x86.AMOVSD
		default:
			panic(fmt.Sprintf("bad float register width %d:%s", t.Size(), t))
		}
	} else {
		switch t.Size() {
		case 1:
			// Avoids partial register write
			return x86.AMOVL
		case 2:
			return x86.AMOVL
		case 4:
			return x86.AMOVL
		default:
			panic(fmt.Sprintf("bad int register width %d:%s", t.Size(), t))
		}
	}
}

// loadByType returns the load instruction of the given type.
func loadByType(t ssa.Type) obj.As {
	// Avoid partial register write
	if !t.IsFloat() && t.Size() <= 2 {
		if t.Size() == 1 {
			return x86.AMOVBLZX
		} else {
			return x86.AMOVWLZX
		}
	}
	// Otherwise, there's no difference between load and store opcodes.
	return storeByType(t)
}

// storeByType returns the store instruction of the given type.
func storeByType(t ssa.Type) obj.As {
	if t.IsFloat() {
		switch t.Size() {
		case 4:
			return arm.AMOVF
		case 8:
			return arm.AMOVD
		}
	} else {
		switch t.Size() {
		case 1:
			return arm.AMOVB
		case 2:
			return arm.AMOVH
		case 4:
			return arm.AMOVW
		}
	}
	panic("bad store type")
}

// loadPush returns the opcode for load+push of the given type.
func loadPush(t ssa.Type) obj.As {
	if t.Size() == 4 {
		return x86.AFMOVF
	}
	return x86.AFMOVD
}

// loadByType returns the load instruction of the given type.
func loadByType(t ssa.Type, r int16) obj.As {
	if mips.REG_F0 <= r && r <= mips.REG_F31 {
		if t.IsFloat() && t.Size() == 4 { // float32
			return mips.AMOVF
		} else { // float64 or integer in FP register
			return mips.AMOVD
		}
	} else {
		switch t.Size() {
		case 1:
			if t.IsSigned() {
				return mips.AMOVB
			} else {
				return mips.AMOVBU
			}
		case 2:
			if t.IsSigned() {
				return mips.AMOVH
			} else {
				return mips.AMOVHU
			}
		case 4:
			if t.IsSigned() {
				return mips.AMOVW
			} else {
				return mips.AMOVWU
			}
		case 8:
			return mips.AMOVV
		}
	}
	panic("bad load type")
}