cli/q
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Implemented 32-bit jumps

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This commit is contained in:
Eduard Urbach 2024-07-10 15:01:46 +02:00
parent d3436b13a5
commit e24d9ebb50
Signed by: akyoto
GPG Key ID: C874F672B1AF20C0
10 changed files with 253 additions and 38 deletions
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13
examples/write/write.q
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@ -1,13 +0,0 @@
main() {
address := 4194304 + 1
length := 3
print(address, length)
}
print(address, length) {
write(1, address, length)
}
write(fd, address, length) {
syscall(1, fd, address, length)
}

2
src/build/arch/x64/Call.go
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@ -5,7 +5,7 @@ package x64
func Call(code []byte, address uint32) []byte {
return append(
code,
0xe8,
0xE8,
byte(address),
byte(address>>8),
byte(address>>16),

22
src/build/arch/x64/Jump.go
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@ -3,43 +3,35 @@ package x64
// Jump continues program flow at the new address.
// The address is relative to the next instruction.
func Jump8(code []byte, address int8) []byte {
return jump8(code, 0xEB, address)
return append(code, 0xEB, byte(address))
}
// JumpIfLess jumps if the result was less.
func Jump8IfLess(code []byte, address int8) []byte {
return jump8(code, 0x7C, address)
return append(code, 0x7C, byte(address))
}
// JumpIfLessOrEqual jumps if the result was less or equal.
func Jump8IfLessOrEqual(code []byte, address int8) []byte {
return jump8(code, 0x7E, address)
return append(code, 0x7E, byte(address))
}
// JumpIfGreater jumps if the result was greater.
func Jump8IfGreater(code []byte, address int8) []byte {
return jump8(code, 0x7F, address)
return append(code, 0x7F, byte(address))
}
// JumpIfGreaterOrEqual jumps if the result was greater or equal.
func Jump8IfGreaterOrEqual(code []byte, address int8) []byte {
return jump8(code, 0x7D, address)
return append(code, 0x7D, byte(address))
}
// JumpIfEqual jumps if the result was equal.
func Jump8IfEqual(code []byte, address int8) []byte {
return jump8(code, 0x74, address)
return append(code, 0x74, byte(address))
}
// JumpIfNotEqual jumps if the result was not equal.
func Jump8IfNotEqual(code []byte, address int8) []byte {
return jump8(code, 0x75, address)
}
func jump8(code []byte, opCode byte, address int8) []byte {
return append(
code,
opCode,
byte(address),
)
return append(code, 0x75, byte(address))
}

2
src/build/arch/x64/SizeOf.go
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@ -3,7 +3,7 @@ package x64
import "math"
// SizeOf tells you how many bytes are needed to encode this number.
func SizeOf(number int) int {
func SizeOf(number int64) int {
switch {
case number >= math.MinInt8 && number <= math.MaxInt8:
return 1

2
src/build/arch/x64/regRegNum.go
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@ -4,7 +4,7 @@ import "encoding/binary"
// regRegNum encodes an instruction with up to two registers and a number parameter.
func regRegNum(code []byte, reg byte, rm byte, number int, opCode8 byte, opCode32 byte) []byte {
if SizeOf(number) == 1 {
if SizeOf(int64(number)) == 1 {
code = regReg(code, reg, rm, opCode8)
return append(code, byte(number))
}

58
src/build/asm/Assembler.go
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@ -2,6 +2,7 @@ package asm
import (
"encoding/binary"
"fmt"
"git.akyoto.dev/cli/q/src/build/arch/x64"
)
@ -16,7 +17,7 @@ func (a Assembler) Finalize() ([]byte, []byte) {
code := make([]byte, 0, len(a.Instructions)*8)
data := make([]byte, 0, 16)
labels := map[string]Address{}
pointers := []Pointer{}
pointers := []*Pointer{}
for _, x := range a.Instructions {
switch x.Mnemonic {
@ -53,8 +54,9 @@ func (a Assembler) Finalize() ([]byte, []byte) {
label := x.Data.(*Label)
nextInstructionAddress := Address(len(code))
pointers = append(pointers, Pointer{
pointers = append(pointers, &Pointer{
Position: Address(len(code) - size),
OpSize: 1,
Size: uint8(size),
Resolve: func() Address {
destination, exists := labels[label.Name]
@ -101,8 +103,9 @@ func (a Assembler) Finalize() ([]byte, []byte) {
label := x.Data.(*Label)
nextInstructionAddress := Address(len(code))
pointers = append(pointers, Pointer{
pointers = append(pointers, &Pointer{
Position: Address(len(code) - size),
OpSize: 1,
Size: uint8(size),
Resolve: func() Address {
destination, exists := labels[label.Name]
@ -153,10 +156,55 @@ func (a Assembler) Finalize() ([]byte, []byte) {
// dataStart := config.BaseAddress + config.CodeOffset + Address(len(code))
for _, pointer := range pointers {
slice := code[pointer.Position : pointer.Position+Address(pointer.Size)]
restart:
for i, pointer := range pointers {
address := pointer.Resolve()
if x64.SizeOf(int64(address)) > int(pointer.Size) {
left := code[:pointer.Position-Address(pointer.OpSize)]
right := code[pointer.Position+Address(pointer.Size):]
size := pointer.Size + pointer.OpSize
opCode := code[pointer.Position-Address(pointer.OpSize)]
var jump []byte
switch opCode {
case 0x74: // JE
jump = []byte{0x0F, 0x84}
case 0x75: // JNE
jump = []byte{0x0F, 0x85}
case 0x7C: // JL
jump = []byte{0x0F, 0x8C}
case 0x7D: // JGE
jump = []byte{0x0F, 0x8D}
case 0x7E: // JLE
jump = []byte{0x0F, 0x8E}
case 0x7F: // JG
jump = []byte{0x0F, 0x8F}
case 0xEB: // JMP
jump = []byte{0xE9}
default:
panic(fmt.Errorf("failed to increase pointer size for instruction 0x%x", opCode))
}
pointer.Position += Address(len(jump) - int(pointer.OpSize))
pointer.OpSize = uint8(len(jump))
pointer.Size = 4
jump = binary.LittleEndian.AppendUint32(jump, uint32(address))
offset := Address(len(jump)) - Address(size)
for _, following := range pointers[i+1:] {
following.Position += offset
}
code = append(left, jump...)
code = append(code, right...)
goto restart
}
slice := code[pointer.Position : pointer.Position+Address(pointer.Size)]
switch pointer.Size {
case 1:
slice[0] = uint8(address)

3
src/build/asm/Pointer.go
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@ -1,7 +1,7 @@
package asm
// Address represents a memory address.
type Address = uint32
type Address = int32
// Pointer stores a relative memory address that we can later turn into an absolute one.
// Position: The machine code offset where the address was inserted.
@ -9,5 +9,6 @@ type Address = uint32
type Pointer struct {
Resolve func() Address
Position Address
OpSize uint8
Size uint8
}

1
tests/examples_test.go
View File

@ -11,7 +11,6 @@ var examples = []struct {
ExpectedExitCode int
}{
{"hello", "", 0},
{"write", "ELF", 0},
{"fibonacci", "", 55},
}

187
tests/programs/jump-near.q Normal file
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@ -0,0 +1,187 @@
main() {
x := 10
if x == 0 {
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
}
if x != 10 {
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
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fail()
fail()
fail()
fail()
fail()
}
if x > 10 {
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
}
if x < 10 {
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
}
if x >= 11 {
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
}
if x <= 9 {
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
fail()
}
exit(0)
}
fail() {
exit(1)
}
exit(code) {
syscall(60, code)
}

1
tests/programs_test.go
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@ -30,6 +30,7 @@ var programs = []struct {
{"branch-and", "", 0},
{"branch-or", "", 0},
{"branch-both", "", 0},
{"jump-near", "", 0},
}
func TestPrograms(t *testing.T) {