From f1d4e65c1be2ce8eb6499ce3eefc59a01bf4d8e1 Mon Sep 17 00:00:00 2001
From: Eduard Urbach <admin@akyoto.dev>
Date: Sun, 28 Jul 2024 21:09:42 +0200
Subject: [PATCH] Implemented move with sign extension

---
 src/build/arch/x64/Move.go      | 22 +++++++++++++++++++++-
 src/build/arch/x64/Move_test.go | 20 ++++++++++++++++++++
 tests/programs/negation.q       |  2 +-
 tests/programs/negative.q       |  2 +-
 tests/programs_test.go          |  4 ++--
 5 files changed, 45 insertions(+), 5 deletions(-)

diff --git a/src/build/arch/x64/Move.go b/src/build/arch/x64/Move.go
index ad6dbda..82f5869 100644
--- a/src/build/arch/x64/Move.go
+++ b/src/build/arch/x64/Move.go
@@ -9,12 +9,17 @@ import (
 // MoveRegisterNumber moves an integer into the given register.
 func MoveRegisterNumber(code []byte, destination cpu.Register, number int) []byte {
 	w := byte(0)
-	b := byte(0)
 
 	if SizeOf(int64(number)) == 8 {
 		w = 1
 	}
 
+	if w == 0 && number < 0 {
+		return MoveRegisterNumber32(code, destination, number)
+	}
+
+	b := byte(0)
+
 	if destination > 0b111 {
 		b = 1
 		destination &= 0b111
@@ -33,6 +38,21 @@ func MoveRegisterNumber(code []byte, destination cpu.Register, number int) []byt
 	}
 }
 
+// MoveRegisterNumber32 moves an integer into the given register and sign-extends the register.
+func MoveRegisterNumber32(code []byte, destination cpu.Register, number int) []byte {
+	b := byte(0)
+
+	if destination > 0b111 {
+		b = 1
+		destination &= 0b111
+	}
+
+	code = append(code, REX(1, 0, 0, b))
+	code = append(code, 0xC7)
+	code = append(code, ModRM(AddressDirect, 0, byte(destination)))
+	return binary.LittleEndian.AppendUint32(code, uint32(number))
+}
+
 // MoveRegisterRegister moves a register value into another register.
 func MoveRegisterRegister(code []byte, destination cpu.Register, source cpu.Register) []byte {
 	return encode(code, AddressDirect, source, destination, 8, 0x89)
diff --git a/src/build/arch/x64/Move_test.go b/src/build/arch/x64/Move_test.go
index cbbe134..66cfb4a 100644
--- a/src/build/arch/x64/Move_test.go
+++ b/src/build/arch/x64/Move_test.go
@@ -14,6 +14,7 @@ func TestMoveRegisterNumber(t *testing.T) {
 		Number   int
 		Code     []byte
 	}{
+		// 32 bits
 		{x64.RAX, 0x7FFFFFFF, []byte{0xB8, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.RCX, 0x7FFFFFFF, []byte{0xB9, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.RDX, 0x7FFFFFFF, []byte{0xBA, 0xFF, 0xFF, 0xFF, 0x7F}},
@@ -31,6 +32,7 @@ func TestMoveRegisterNumber(t *testing.T) {
 		{x64.R14, 0x7FFFFFFF, []byte{0x41, 0xBE, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.R15, 0x7FFFFFFF, []byte{0x41, 0xBF, 0xFF, 0xFF, 0xFF, 0x7F}},
 
+		// 64 bits
 		{x64.RAX, 0x7FFFFFFFFFFFFFFF, []byte{0x48, 0xB8, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.RCX, 0x7FFFFFFFFFFFFFFF, []byte{0x48, 0xB9, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.RDX, 0x7FFFFFFFFFFFFFFF, []byte{0x48, 0xBA, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F}},
@@ -47,6 +49,24 @@ func TestMoveRegisterNumber(t *testing.T) {
 		{x64.R13, 0x7FFFFFFFFFFFFFFF, []byte{0x49, 0xBD, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.R14, 0x7FFFFFFFFFFFFFFF, []byte{0x49, 0xBE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F}},
 		{x64.R15, 0x7FFFFFFFFFFFFFFF, []byte{0x49, 0xBF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F}},
+
+		// Negative numbers
+		{x64.RAX, -1, []byte{0x48, 0xC7, 0xC0, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RCX, -1, []byte{0x48, 0xC7, 0xC1, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RDX, -1, []byte{0x48, 0xC7, 0xC2, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RBX, -1, []byte{0x48, 0xC7, 0xC3, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RSP, -1, []byte{0x48, 0xC7, 0xC4, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RBP, -1, []byte{0x48, 0xC7, 0xC5, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RSI, -1, []byte{0x48, 0xC7, 0xC6, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.RDI, -1, []byte{0x48, 0xC7, 0xC7, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R8, -1, []byte{0x49, 0xC7, 0xC0, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R9, -1, []byte{0x49, 0xC7, 0xC1, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R10, -1, []byte{0x49, 0xC7, 0xC2, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R11, -1, []byte{0x49, 0xC7, 0xC3, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R12, -1, []byte{0x49, 0xC7, 0xC4, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R13, -1, []byte{0x49, 0xC7, 0xC5, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R14, -1, []byte{0x49, 0xC7, 0xC6, 0xFF, 0xFF, 0xFF, 0xFF}},
+		{x64.R15, -1, []byte{0x49, 0xC7, 0xC7, 0xFF, 0xFF, 0xFF, 0xFF}},
 	}
 
 	for _, pattern := range usagePatterns {
diff --git a/tests/programs/negation.q b/tests/programs/negation.q
index aea1133..94e2826 100644
--- a/tests/programs/negation.q
+++ b/tests/programs/negation.q
@@ -1,5 +1,5 @@
 main() {
-	syscall(60, f(-32))
+	assert f(-32) == 32
 }
 
 f(x) {
diff --git a/tests/programs/negative.q b/tests/programs/negative.q
index 2bddfb7..f300e48 100644
--- a/tests/programs/negative.q
+++ b/tests/programs/negative.q
@@ -1,5 +1,5 @@
 main() {
 	a := -32
 	b := 64
-	syscall(60, a + b)
+	assert a + b == 32
 }
\ No newline at end of file
diff --git a/tests/programs_test.go b/tests/programs_test.go
index 3a2d801..932c085 100644
--- a/tests/programs_test.go
+++ b/tests/programs_test.go
@@ -31,8 +31,8 @@ var programs = []struct {
 	{"modulo", "", "", 0},
 	{"modulo-assign", "", "", 0},
 	{"division-split", "", "", 0},
-	{"negative", "", "", 32},
-	{"negation", "", "", 32},
+	{"negative", "", "", 0},
+	{"negation", "", "", 0},
 	{"square-sum", "", "", 0},
 	{"chained-calls", "", "", 0},
 	{"nested-calls", "", "", 0},