From 7c28296f92d479df307a36efbf8f5665b0d81944 Mon Sep 17 00:00:00 2001
From: sergeych <real.sergeych@gmail.com>
Date: Mon, 16 Feb 2026 17:42:04 +0300
Subject: [PATCH] Elide redundant bool conversions in logical ops

---
 .../lyng/bytecode/BytecodeCompiler.kt         | 40 ++++---------------
 notes/fast_ops_optimizations_plan.md          |  5 ++-
 2 files changed, 11 insertions(+), 34 deletions(-)

diff --git a/lynglib/src/commonMain/kotlin/net/sergeych/lyng/bytecode/BytecodeCompiler.kt b/lynglib/src/commonMain/kotlin/net/sergeych/lyng/bytecode/BytecodeCompiler.kt
index 523911a..7920f0d 100644
--- a/lynglib/src/commonMain/kotlin/net/sergeych/lyng/bytecode/BytecodeCompiler.kt
+++ b/lynglib/src/commonMain/kotlin/net/sergeych/lyng/bytecode/BytecodeCompiler.kt
@@ -2339,60 +2339,36 @@ class BytecodeCompiler(
 
     private fun compileLogicalAnd(ref: LogicalAndRef): CompiledValue? {
         val leftValue = compileRefWithFallback(ref.left(), SlotType.BOOL, Pos.builtIn) ?: return null
-        val leftBool = if (leftValue.type == SlotType.BOOL) {
-            leftValue
-        } else {
-            val slot = allocSlot()
-            builder.emit(Opcode.OBJ_TO_BOOL, leftValue.slot, slot)
-            CompiledValue(slot, SlotType.BOOL)
-        }
+        if (leftValue.type != SlotType.BOOL) return null
         val resultSlot = allocSlot()
         val falseId = builder.addConst(BytecodeConst.Bool(false))
         builder.emit(Opcode.CONST_BOOL, falseId, resultSlot)
         val endLabel = builder.label()
         builder.emit(
             Opcode.JMP_IF_FALSE,
-            listOf(CmdBuilder.Operand.IntVal(leftBool.slot), CmdBuilder.Operand.LabelRef(endLabel))
+            listOf(CmdBuilder.Operand.IntVal(leftValue.slot), CmdBuilder.Operand.LabelRef(endLabel))
         )
         val rightValue = compileRefWithFallback(ref.right(), SlotType.BOOL, Pos.builtIn) ?: return null
-        val rightBool = if (rightValue.type == SlotType.BOOL) {
-            rightValue
-        } else {
-            val slot = allocSlot()
-            builder.emit(Opcode.OBJ_TO_BOOL, rightValue.slot, slot)
-            CompiledValue(slot, SlotType.BOOL)
-        }
-        builder.emit(Opcode.MOVE_BOOL, rightBool.slot, resultSlot)
+        if (rightValue.type != SlotType.BOOL) return null
+        builder.emit(Opcode.MOVE_BOOL, rightValue.slot, resultSlot)
         builder.mark(endLabel)
         return CompiledValue(resultSlot, SlotType.BOOL)
     }
 
     private fun compileLogicalOr(ref: LogicalOrRef): CompiledValue? {
         val leftValue = compileRefWithFallback(ref.left(), SlotType.BOOL, Pos.builtIn) ?: return null
-        val leftBool = if (leftValue.type == SlotType.BOOL) {
-            leftValue
-        } else {
-            val slot = allocSlot()
-            builder.emit(Opcode.OBJ_TO_BOOL, leftValue.slot, slot)
-            CompiledValue(slot, SlotType.BOOL)
-        }
+        if (leftValue.type != SlotType.BOOL) return null
         val resultSlot = allocSlot()
         val trueId = builder.addConst(BytecodeConst.Bool(true))
         builder.emit(Opcode.CONST_BOOL, trueId, resultSlot)
         val endLabel = builder.label()
         builder.emit(
             Opcode.JMP_IF_TRUE,
-            listOf(CmdBuilder.Operand.IntVal(leftBool.slot), CmdBuilder.Operand.LabelRef(endLabel))
+            listOf(CmdBuilder.Operand.IntVal(leftValue.slot), CmdBuilder.Operand.LabelRef(endLabel))
         )
         val rightValue = compileRefWithFallback(ref.right(), SlotType.BOOL, Pos.builtIn) ?: return null
-        val rightBool = if (rightValue.type == SlotType.BOOL) {
-            rightValue
-        } else {
-            val slot = allocSlot()
-            builder.emit(Opcode.OBJ_TO_BOOL, rightValue.slot, slot)
-            CompiledValue(slot, SlotType.BOOL)
-        }
-        builder.emit(Opcode.MOVE_BOOL, rightBool.slot, resultSlot)
+        if (rightValue.type != SlotType.BOOL) return null
+        builder.emit(Opcode.MOVE_BOOL, rightValue.slot, resultSlot)
         builder.mark(endLabel)
         return CompiledValue(resultSlot, SlotType.BOOL)
     }
diff --git a/notes/fast_ops_optimizations_plan.md b/notes/fast_ops_optimizations_plan.md
index cbe8d64..def0503 100644
--- a/notes/fast_ops_optimizations_plan.md
+++ b/notes/fast_ops_optimizations_plan.md
@@ -10,8 +10,9 @@ Candidates (not started)
 2) Mixed numeric ops (done)
    - Allow INT+REAL arithmetic to use primitive REAL ops (no obj fallback).
    - MixedCompareBenchmarkTest: 347 ms -> 275 ms.
-3) Boolean conversion
-   - Skip OBJ_TO_BOOL when compiler already has a BOOL slot.
+3) Boolean conversion (done; do not revert without review)
+   - Skip redundant OBJ_TO_BOOL in logical AND/OR when compiler already emits BOOL.
+   - MixedCompareBenchmarkTest: 275 ms -> 249 ms.
 4) Range/loop hot path
    - Keep range iteration in INT ops, avoid accidental boxing.
    - Confirm loop-var slots avoid re-boxing in loop bodies.