From 62747cb3a6542cb4af0be05dd5a79acc564e6cd0 Mon Sep 17 00:00:00 2001
From: Haled Odat <8566042+HalidOdat@users.noreply.github.com>
Date: Thu, 2 Apr 2026 18:57:50 +0200
Subject: [PATCH] feat(compiler): Generate optimized code for ToInt32 code
 patterns

---
 .../src/bytecompiler/expression/binary.rs     | 24 ++++++++++++---
 core/engine/src/vm/code_block.rs              |  4 +--
 core/engine/src/vm/flowgraph/mod.rs           |  4 +--
 core/engine/src/vm/opcode/mod.rs              |  9 ++++--
 core/engine/src/vm/opcode/unary_ops/mod.rs    | 29 +++++++++++++++++++
 5 files changed, 60 insertions(+), 10 deletions(-)

diff --git a/core/engine/src/bytecompiler/expression/binary.rs b/core/engine/src/bytecompiler/expression/binary.rs
index 66a80a2d415..b603c149cf8 100644
--- a/core/engine/src/bytecompiler/expression/binary.rs
+++ b/core/engine/src/bytecompiler/expression/binary.rs
@@ -4,9 +4,12 @@ use crate::{
 };
 use boa_ast::{
     Expression,
-    expression::operator::{
-        Binary, BinaryInPrivate,
-        binary::{ArithmeticOp, BinaryOp, BitwiseOp, LogicalOp, RelationalOp},
+    expression::{
+        literal::LiteralKind,
+        operator::{
+            Binary, BinaryInPrivate,
+            binary::{ArithmeticOp, BinaryOp, BitwiseOp, LogicalOp, RelationalOp},
+        },
     },
 };
 
@@ -20,7 +23,20 @@ impl ByteCompiler<'_> {
             }
             BinaryOp::Bitwise(op) => {
                 self.compile_expr_operand(binary.lhs(), |self_, lhs| {
-                    self_.compile_binary_bitwise(op, binary.rhs(), dst, lhs);
+                    const MAX_UINT32_LITERAL: LiteralKind = LiteralKind::Num(u32::MAX as f64);
+                    if let Expression::Literal(literal) = binary.rhs().flatten()
+                        && (
+                            // x | 0
+                            (op == BitwiseOp::Or && literal.kind() == &LiteralKind::Int(0))
+                            ||
+                            // x & 0xFFFFFFFF
+                            (op == BitwiseOp::And && literal.kind() == &MAX_UINT32_LITERAL)
+                        )
+                    {
+                        self_.bytecode.emit_to_int32(dst.variable(), lhs);
+                    } else {
+                        self_.compile_binary_bitwise(op, binary.rhs(), dst, lhs);
+                    }
                 });
             }
             BinaryOp::Relational(op) => {
diff --git a/core/engine/src/vm/code_block.rs b/core/engine/src/vm/code_block.rs
index d9eec2fc949..a6e3fb893e6 100644
--- a/core/engine/src/vm/code_block.rs
+++ b/core/engine/src/vm/code_block.rs
@@ -396,6 +396,7 @@ impl CodeBlock {
             | Instruction::CreateUnmappedArgumentsObject { dst }
             | Instruction::RestParameterInit { dst }
             | Instruction::StoreNewArray { dst } => format!("dst:{dst}"),
+            Instruction::ToInt32 { dst, src } => format!("dst:{dst}, src:{src}"),
             Instruction::Add { lhs, rhs, dst }
             | Instruction::Sub { lhs, rhs, dst }
             | Instruction::Div { lhs, rhs, dst }
@@ -933,8 +934,7 @@ impl CodeBlock {
             | Instruction::Reserved56
             | Instruction::Reserved57
             | Instruction::Reserved58
-            | Instruction::Reserved59
-            | Instruction::Reserved60 => unreachable!("Reserved opcodes are unreachable"),
+            | Instruction::Reserved59 => unreachable!("Reserved opcodes are unreachable"),
         }
     }
 }
diff --git a/core/engine/src/vm/flowgraph/mod.rs b/core/engine/src/vm/flowgraph/mod.rs
index 2f96e6edcbd..da8ff98f25f 100644
--- a/core/engine/src/vm/flowgraph/mod.rs
+++ b/core/engine/src/vm/flowgraph/mod.rs
@@ -46,6 +46,7 @@ impl CodeBlock {
                 | Instruction::Move { .. }
                 | Instruction::PopIntoRegister { .. }
                 | Instruction::PushFromRegister { .. }
+                | Instruction::ToInt32 { .. }
                 | Instruction::Add { .. }
                 | Instruction::Sub { .. }
                 | Instruction::Div { .. }
@@ -432,8 +433,7 @@ impl CodeBlock {
                 | Instruction::Reserved56
                 | Instruction::Reserved57
                 | Instruction::Reserved58
-                | Instruction::Reserved59
-                | Instruction::Reserved60 => unreachable!("Reserved opcodes are unreachable"),
+                | Instruction::Reserved59 => unreachable!("Reserved opcodes are unreachable"),
             }
         }
 
diff --git a/core/engine/src/vm/opcode/mod.rs b/core/engine/src/vm/opcode/mod.rs
index f01c7afecbe..37cb4940311 100644
--- a/core/engine/src/vm/opcode/mod.rs
+++ b/core/engine/src/vm/opcode/mod.rs
@@ -767,6 +767,13 @@ generate_opcodes! {
     ///   - Input: array
     PushIteratorToArray { array: RegisterOperand },
 
+    /// Convert the value into a int32.
+    ///
+    /// - Registers
+    ///   - Input: src
+    ///   - Output: dst
+    ToInt32 { dst: RegisterOperand, src: RegisterOperand },
+
     /// Binary `+` operator.
     ///
     /// - Registers
@@ -2270,6 +2277,4 @@ generate_opcodes! {
     Reserved58 => Reserved,
     /// Reserved [`Opcode`].
     Reserved59 => Reserved,
-    /// Reserved [`Opcode`].
-    Reserved60 => Reserved,
 }
diff --git a/core/engine/src/vm/opcode/unary_ops/mod.rs b/core/engine/src/vm/opcode/unary_ops/mod.rs
index d2ed6920956..15a5afa61ac 100644
--- a/core/engine/src/vm/opcode/unary_ops/mod.rs
+++ b/core/engine/src/vm/opcode/unary_ops/mod.rs
@@ -123,3 +123,32 @@ impl Operation for BitNot {
     const INSTRUCTION: &'static str = "INST - BitNot";
     const COST: u8 = 3;
 }
+
+/// `ToInt32` implements the Opcode Operation for `Opcode::ToInt32`
+///
+/// Operation:
+///  - Unary bitwise `~` operator.
+#[derive(Debug, Clone, Copy)]
+pub(crate) struct ToInt32;
+
+impl ToInt32 {
+    #[inline(always)]
+    pub(super) fn operation(
+        (dst, src): (RegisterOperand, RegisterOperand),
+        context: &mut Context,
+    ) -> JsResult<()> {
+        let result = context
+            .vm
+            .get_register(src.into())
+            .clone()
+            .to_i32(context)?;
+        context.vm.set_register(dst.into(), result.into());
+        Ok(())
+    }
+}
+
+impl Operation for ToInt32 {
+    const NAME: &'static str = "ToInt32";
+    const INSTRUCTION: &'static str = "INST - ToInt32";
+    const COST: u8 = 1;
+}