diff --git a/codeGenCpu6502/src/prog8/codegen/cpu6502/AsmGen.kt b/codeGenCpu6502/src/prog8/codegen/cpu6502/AsmGen.kt
index d8db59e6e..355f313da 100644
--- a/codeGenCpu6502/src/prog8/codegen/cpu6502/AsmGen.kt
+++ b/codeGenCpu6502/src/prog8/codegen/cpu6502/AsmGen.kt
@@ -1,7 +1,10 @@
 package prog8.codegen.cpu6502
 
 import com.github.michaelbull.result.fold
-import prog8.ast.*
+import prog8.ast.IFunctionCall
+import prog8.ast.Node
+import prog8.ast.ParentSentinel
+import prog8.ast.Program
 import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
@@ -10,7 +13,6 @@ import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.*
 import prog8.compiler.BuiltinFunctions
 import prog8.compiler.builtinFunctionReturnType
-import prog8.code.core.SourceCode
 import java.util.*
 import kotlin.io.path.Path
 import kotlin.io.path.writeLines
diff --git a/codeGenCpu6502/src/prog8/codegen/cpu6502/AssemblyProgram.kt b/codeGenCpu6502/src/prog8/codegen/cpu6502/AssemblyProgram.kt
index 85896dbf5..da518f042 100644
--- a/codeGenCpu6502/src/prog8/codegen/cpu6502/AssemblyProgram.kt
+++ b/codeGenCpu6502/src/prog8/codegen/cpu6502/AssemblyProgram.kt
@@ -4,7 +4,6 @@ import com.github.michaelbull.result.Ok
 import com.github.michaelbull.result.Result
 import com.github.michaelbull.result.mapError
 import prog8.code.core.*
-import prog8.code.core.SourceCode
 import java.io.File
 import java.nio.file.Path
 import kotlin.io.path.Path
diff --git a/codeGenVirtual/src/prog8/codegen/virtual/AssignmentGen.kt b/codeGenVirtual/src/prog8/codegen/virtual/AssignmentGen.kt
index 42e178f31..dceec1f78 100644
--- a/codeGenVirtual/src/prog8/codegen/virtual/AssignmentGen.kt
+++ b/codeGenVirtual/src/prog8/codegen/virtual/AssignmentGen.kt
@@ -28,11 +28,10 @@ internal class AssignmentGen(private val codeGen: CodeGen, private val expressio
             val address = codeGen.allocations.get(ident.targetName)
             assignSelfInMemory(address, assignment.value, assignment)
         } else if(memory != null) {
-            if(memory.address is PtNumber) {
+            if(memory.address is PtNumber)
                 assignSelfInMemory((memory.address as PtNumber).number.toInt(), assignment.value, assignment)
-            } else {
+            else
                 fallbackAssign(assignment)
-            }
         } else if(array!=null) {
             // TODO in-place array element assignment?
             fallbackAssign(assignment)
@@ -58,8 +57,8 @@ internal class AssignmentGen(private val codeGen: CodeGen, private val expressio
                     code // do nothing, mem=mem null assignment.
                 else {
                     // read and write a (i/o) memory location to itself.
-                    code += VmCodeInstruction(Opcode.LOADM, vmDt, reg1 = 0, value = address)
-                    code += VmCodeInstruction(Opcode.STOREM, vmDt, reg1 = 0, value = address)
+                    code += VmCodeInstruction(Opcode.LOADM, vmDt, reg1 =0, value = address)
+                    code += VmCodeInstruction(Opcode.STOREM, vmDt, reg1=0, value = address)
                     code
                 }
             }
diff --git a/codeGenVirtual/src/prog8/codegen/virtual/CodeGen.kt b/codeGenVirtual/src/prog8/codegen/virtual/CodeGen.kt
index a1da9ccd7..a352ae38c 100644
--- a/codeGenVirtual/src/prog8/codegen/virtual/CodeGen.kt
+++ b/codeGenVirtual/src/prog8/codegen/virtual/CodeGen.kt
@@ -208,7 +208,7 @@ class CodeGen(internal val program: PtProgram,
                     // iterate over a zero-terminated string
                     code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=indexReg, value=0)
                     code += VmCodeLabel(loopLabel)
-                    code += VmCodeInstruction(Opcode.LOADX, VmDataType.BYTE, reg1=0, reg2=indexReg, value = arrayAddress)
+                    code += VmCodeInstruction(Opcode.LOADX, VmDataType.BYTE, reg1 = 0, reg2=indexReg, value = arrayAddress)
                     code += VmCodeInstruction(Opcode.BZ, VmDataType.BYTE, reg1=0, labelSymbol = endLabel)
                     code += VmCodeInstruction(Opcode.STOREM, VmDataType.BYTE, reg1=0, value = loopvarAddress)
                     code += translateNode(forLoop.statements)
diff --git a/codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt b/codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt
index 408fdc76c..cd548561f 100644
--- a/codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt
+++ b/codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt
@@ -3,7 +3,9 @@ package prog8.optimizer
 import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.expressions.*
+import prog8.ast.expressions.BinaryExpression
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.TypecastExpression
 import prog8.ast.getTempVar
 import prog8.ast.statements.AssignTarget
 import prog8.ast.statements.Assignment
diff --git a/compiler/src/prog8/compiler/ModuleImporter.kt b/compiler/src/prog8/compiler/ModuleImporter.kt
index 28e417274..fa06feb19 100644
--- a/compiler/src/prog8/compiler/ModuleImporter.kt
+++ b/compiler/src/prog8/compiler/ModuleImporter.kt
@@ -9,8 +9,8 @@ import prog8.ast.statements.Directive
 import prog8.ast.statements.DirectiveArg
 import prog8.code.core.IErrorReporter
 import prog8.code.core.Position
-import prog8.parser.Prog8Parser
 import prog8.code.core.SourceCode
+import prog8.parser.Prog8Parser
 import java.io.File
 import java.nio.file.Path
 import kotlin.io.path.*
diff --git a/compiler/src/prog8/compiler/astprocessing/VerifyFunctionArgTypes.kt b/compiler/src/prog8/compiler/astprocessing/VerifyFunctionArgTypes.kt
index e1c6f5d97..d6088afd3 100644
--- a/compiler/src/prog8/compiler/astprocessing/VerifyFunctionArgTypes.kt
+++ b/compiler/src/prog8/compiler/astprocessing/VerifyFunctionArgTypes.kt
@@ -1,6 +1,9 @@
 package prog8.compiler.astprocessing
 
-import prog8.ast.*
+import prog8.ast.IFunctionCall
+import prog8.ast.IPipe
+import prog8.ast.Node
+import prog8.ast.Program
 import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.Expression
 import prog8.ast.expressions.FunctionCallExpression
diff --git a/compiler/test/ModuleImporterTests.kt b/compiler/test/ModuleImporterTests.kt
index d6a9e6459..f9d8c96e7 100644
--- a/compiler/test/ModuleImporterTests.kt
+++ b/compiler/test/ModuleImporterTests.kt
@@ -11,15 +11,11 @@ import io.kotest.matchers.shouldBe
 import io.kotest.matchers.string.shouldContain
 import prog8.ast.Program
 import prog8.code.core.IErrorReporter
-import prog8.compiler.ModuleImporter
-import prog8.parser.ParseError
 import prog8.code.core.SourceCode
 import prog8.code.core.internedStringsModuleName
-import prog8tests.helpers.Helpers
-import prog8tests.helpers.DummyFunctions
-import prog8tests.helpers.DummyMemsizer
-import prog8tests.helpers.DummyStringEncoder
-import prog8tests.helpers.ErrorReporterForTests
+import prog8.compiler.ModuleImporter
+import prog8.parser.ParseError
+import prog8tests.helpers.*
 import kotlin.io.path.*
 
 
diff --git a/compiler/test/TestCallgraph.kt b/compiler/test/TestCallgraph.kt
index d3fdfa33d..b087a8280 100644
--- a/compiler/test/TestCallgraph.kt
+++ b/compiler/test/TestCallgraph.kt
@@ -9,10 +9,10 @@ import io.kotest.matchers.string.shouldContain
 import prog8.ast.Program
 import prog8.ast.statements.Block
 import prog8.ast.statements.Subroutine
+import prog8.code.core.SourceCode
 import prog8.code.target.C64Target
 import prog8.compiler.CallGraph
 import prog8.parser.Prog8Parser.parseModule
-import prog8.code.core.SourceCode
 import prog8tests.helpers.*
 
 class TestCallgraph: FunSpec({
diff --git a/compiler/test/TestCompilerOnExamples.kt b/compiler/test/TestCompilerOnExamples.kt
index d5202b0ff..a722142bd 100644
--- a/compiler/test/TestCompilerOnExamples.kt
+++ b/compiler/test/TestCompilerOnExamples.kt
@@ -8,8 +8,8 @@ import prog8.code.target.Cx16Target
 import prog8.compiler.CompilationResult
 import prog8.compiler.CompilerArguments
 import prog8.compiler.compileProgram
-import prog8tests.helpers.Helpers
 import prog8tests.helpers.Combinations
+import prog8tests.helpers.Helpers
 import java.nio.file.Path
 import kotlin.io.path.absolute
 import kotlin.io.path.exists
diff --git a/compiler/test/TestCompilerOnImportsAndIncludes.kt b/compiler/test/TestCompilerOnImportsAndIncludes.kt
index 1852de970..d3ec21fc4 100644
--- a/compiler/test/TestCompilerOnImportsAndIncludes.kt
+++ b/compiler/test/TestCompilerOnImportsAndIncludes.kt
@@ -10,7 +10,8 @@ import prog8.ast.expressions.StringLiteral
 import prog8.ast.statements.FunctionCallStatement
 import prog8.ast.statements.Label
 import prog8.code.target.Cx16Target
-import prog8tests.helpers.*
+import prog8tests.helpers.Helpers
+import prog8tests.helpers.compileFile
 import kotlin.io.path.name
 
 
diff --git a/compiler/test/TestCompilerOnRanges.kt b/compiler/test/TestCompilerOnRanges.kt
index cfc8cf0f6..31e3b39d4 100644
--- a/compiler/test/TestCompilerOnRanges.kt
+++ b/compiler/test/TestCompilerOnRanges.kt
@@ -17,8 +17,8 @@ import prog8.code.core.Encoding
 import prog8.code.core.Position
 import prog8.code.target.C64Target
 import prog8.code.target.Cx16Target
-import prog8tests.helpers.ErrorReporterForTests
 import prog8tests.helpers.Combinations
+import prog8tests.helpers.ErrorReporterForTests
 import prog8tests.helpers.compileText
 
 
diff --git a/compiler/test/TestMemory.kt b/compiler/test/TestMemory.kt
index 198d0b55d..f7f5a006d 100644
--- a/compiler/test/TestMemory.kt
+++ b/compiler/test/TestMemory.kt
@@ -12,10 +12,10 @@ import prog8.ast.expressions.PrefixExpression
 import prog8.ast.statements.*
 import prog8.code.core.DataType
 import prog8.code.core.Position
+import prog8.code.core.SourceCode
 import prog8.code.core.ZeropageWish
 import prog8.code.target.C64Target
 import prog8.compiler.printProgram
-import prog8.code.core.SourceCode
 import prog8tests.helpers.DummyFunctions
 import prog8tests.helpers.DummyMemsizer
 import prog8tests.helpers.DummyStringEncoder
diff --git a/compiler/test/TestPipes.kt b/compiler/test/TestPipes.kt
index c60099b4b..337b7b44a 100644
--- a/compiler/test/TestPipes.kt
+++ b/compiler/test/TestPipes.kt
@@ -13,11 +13,11 @@ import prog8.ast.statements.Pipe
 import prog8.ast.statements.VarDecl
 import prog8.code.core.DataType
 import prog8.code.core.Position
+import prog8.code.core.SourceCode
 import prog8.code.target.C64Target
+import prog8.code.target.VMTarget
 import prog8.compiler.astprocessing.AstPreprocessor
 import prog8.parser.Prog8Parser.parseModule
-import prog8.code.core.SourceCode
-import prog8.code.target.VMTarget
 import prog8tests.helpers.*
 
 
diff --git a/compiler/test/ast/TestAstToSourceText.kt b/compiler/test/ast/TestAstToSourceText.kt
index 5eb917313..76a7dbfed 100644
--- a/compiler/test/ast/TestAstToSourceText.kt
+++ b/compiler/test/ast/TestAstToSourceText.kt
@@ -6,10 +6,10 @@ import io.kotest.matchers.string.shouldContain
 import prog8.ast.AstToSourceTextConverter
 import prog8.ast.Module
 import prog8.ast.Program
-import prog8.parser.ParseError
-import prog8.parser.Prog8Parser.parseModule
 import prog8.code.core.SourceCode
 import prog8.code.core.internedStringsModuleName
+import prog8.parser.ParseError
+import prog8.parser.Prog8Parser.parseModule
 import prog8tests.helpers.DummyFunctions
 import prog8tests.helpers.DummyMemsizer
 import prog8tests.helpers.DummyStringEncoder
diff --git a/compiler/test/ast/TestIdentifierRef.kt b/compiler/test/ast/TestIdentifierRef.kt
index 7d27d04c3..1839fe5a8 100644
--- a/compiler/test/ast/TestIdentifierRef.kt
+++ b/compiler/test/ast/TestIdentifierRef.kt
@@ -10,8 +10,8 @@ import prog8.ast.expressions.NumericLiteral
 import prog8.ast.expressions.PrefixExpression
 import prog8.ast.statements.*
 import prog8.code.core.Position
-import prog8.parser.Prog8Parser
 import prog8.code.core.SourceCode
+import prog8.parser.Prog8Parser
 import prog8tests.helpers.DummyFunctions
 import prog8tests.helpers.DummyMemsizer
 import prog8tests.helpers.DummyStringEncoder
diff --git a/compiler/test/ast/TestIntermediateAst.kt b/compiler/test/ast/TestIntermediateAst.kt
index 3464529d0..6fc2ffa85 100644
--- a/compiler/test/ast/TestIntermediateAst.kt
+++ b/compiler/test/ast/TestIntermediateAst.kt
@@ -6,7 +6,6 @@ import io.kotest.matchers.ints.shouldBeGreaterThan
 import io.kotest.matchers.shouldBe
 import prog8.code.ast.*
 import prog8.code.core.DataType
-import prog8.code.core.Position
 import prog8.code.target.C64Target
 import prog8.compiler.IntermediateAstMaker
 import prog8tests.helpers.compileText
diff --git a/compiler/test/ast/TestProg8Parser.kt b/compiler/test/ast/TestProg8Parser.kt
index d2a93fde7..521983e53 100644
--- a/compiler/test/ast/TestProg8Parser.kt
+++ b/compiler/test/ast/TestProg8Parser.kt
@@ -17,15 +17,11 @@ import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.code.core.DataType
-import prog8.code.core.Encoding
-import prog8.code.core.Position
-import prog8.code.core.ZeropageWish
+import prog8.code.core.*
 import prog8.code.target.C64Target
 import prog8.code.target.cbm.PetsciiEncoding
 import prog8.parser.ParseError
 import prog8.parser.Prog8Parser.parseModule
-import prog8.code.core.SourceCode
 import prog8tests.helpers.*
 import kotlin.io.path.Path
 import kotlin.io.path.isRegularFile
diff --git a/compiler/test/ast/TestSubroutines.kt b/compiler/test/ast/TestSubroutines.kt
index 4a4bd3927..45227e62c 100644
--- a/compiler/test/ast/TestSubroutines.kt
+++ b/compiler/test/ast/TestSubroutines.kt
@@ -5,8 +5,8 @@ import io.kotest.matchers.shouldBe
 import prog8.ast.statements.Block
 import prog8.ast.statements.Subroutine
 import prog8.code.core.DataType
-import prog8.parser.Prog8Parser.parseModule
 import prog8.code.core.SourceCode
+import prog8.parser.Prog8Parser.parseModule
 
 
 class TestSubroutines: AnnotationSpec() {
diff --git a/compiler/test/ast/TestVarious.kt b/compiler/test/ast/TestVarious.kt
index f3eb74adb..e602bfd32 100644
--- a/compiler/test/ast/TestVarious.kt
+++ b/compiler/test/ast/TestVarious.kt
@@ -6,7 +6,6 @@ import io.kotest.matchers.shouldNotBe
 import prog8.ast.IFunctionCall
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.StringLiteral
-import prog8.ast.statements.Assignment
 import prog8.ast.statements.InlineAssembly
 import prog8.ast.statements.VarDecl
 import prog8.code.core.Position
diff --git a/compiler/test/codegeneration/TestAsmGenSymbols.kt b/compiler/test/codegeneration/TestAsmGenSymbols.kt
index 0dbbcb16f..8fdf583d1 100644
--- a/compiler/test/codegeneration/TestAsmGenSymbols.kt
+++ b/compiler/test/codegeneration/TestAsmGenSymbols.kt
@@ -13,7 +13,6 @@ import prog8.code.target.C64Target
 import prog8.code.target.c64.C64Zeropage
 import prog8.codegen.cpu6502.AsmGen
 import prog8.compiler.astprocessing.SymbolTableMaker
-import prog8.code.core.SourceCode
 import prog8tests.helpers.DummyFunctions
 import prog8tests.helpers.DummyMemsizer
 import prog8tests.helpers.DummyStringEncoder
diff --git a/compilerAst/src/prog8/ast/Program.kt b/compilerAst/src/prog8/ast/Program.kt
index 9ca9a1839..8d09c0b11 100644
--- a/compilerAst/src/prog8/ast/Program.kt
+++ b/compilerAst/src/prog8/ast/Program.kt
@@ -6,7 +6,6 @@ import prog8.ast.expressions.StringLiteral
 import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
 import prog8.code.core.*
-import prog8.code.core.SourceCode
 
 /*********** Everything starts from here, the Program; zero or more modules *************/
 
diff --git a/compilerAst/src/prog8/ast/antlr/Antlr2Kotlin.kt b/compilerAst/src/prog8/ast/antlr/Antlr2Kotlin.kt
index 9c6aeb74d..2984c0a4e 100644
--- a/compilerAst/src/prog8/ast/antlr/Antlr2Kotlin.kt
+++ b/compilerAst/src/prog8/ast/antlr/Antlr2Kotlin.kt
@@ -8,7 +8,6 @@ import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.code.core.*
 import prog8.parser.Prog8ANTLRParser
-import prog8.code.core.SourceCode
 import java.nio.file.Path
 import kotlin.io.path.isRegularFile
 
diff --git a/compilerAst/src/prog8/ast/expressions/AstExpressions.kt b/compilerAst/src/prog8/ast/expressions/AstExpressions.kt
index 1ab326b15..11338a502 100644
--- a/compilerAst/src/prog8/ast/expressions/AstExpressions.kt
+++ b/compilerAst/src/prog8/ast/expressions/AstExpressions.kt
@@ -1,6 +1,9 @@
 package prog8.ast.expressions
 
-import prog8.ast.*
+import prog8.ast.IFunctionCall
+import prog8.ast.IPipe
+import prog8.ast.Node
+import prog8.ast.Program
 import prog8.ast.base.ExpressionError
 import prog8.ast.base.FatalAstException
 import prog8.ast.base.UndefinedSymbolError
diff --git a/compilerAst/src/prog8/compiler/BuiltinFunctions.kt b/compilerAst/src/prog8/compiler/BuiltinFunctions.kt
index 75fd4b0a8..48ecb8614 100644
--- a/compilerAst/src/prog8/compiler/BuiltinFunctions.kt
+++ b/compilerAst/src/prog8/compiler/BuiltinFunctions.kt
@@ -7,7 +7,10 @@ import prog8.ast.base.SyntaxError
 import prog8.ast.expressions.*
 import prog8.ast.statements.VarDecl
 import prog8.code.core.*
-import kotlin.math.*
+import kotlin.math.abs
+import kotlin.math.floor
+import kotlin.math.sign
+import kotlin.math.sqrt
 
 
 private typealias ConstExpressionCaller = (args: List<Expression>, position: Position, program: Program) -> NumericLiteral
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index 6e7d30cd4..f7ba6dee7 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -3,7 +3,8 @@ TODO
 
 For next release
 ^^^^^^^^^^^^^^^^
-- add McCarthy evaluation to shortcircuit and/or expressions. First do ifs by splitting them up? Then do expressions that compute a value?
+- vm: don't use register 0/1 "as convenience" where it's not required, just allocate a new register anyway.
+      search for reg.\s?=\s?0
 
 ...
 
@@ -19,11 +20,12 @@ Future Things and Ideas
 ^^^^^^^^^^^^^^^^^^^^^^^
 Compiler:
 
+- add McCarthy evaluation to shortcircuit and/or expressions. First do ifs by splitting them up? Then do expressions that compute a value?
 - vm: codeGen: various TODOs to tweak code
 - vm: implement remaining sin/cos functions in math.p8
 - vm: somehow deal with asmsubs otherwise the vm IR can't fully encode all of prog8
 - vm: don't store symbol names in instructions to make optimizing the IR easier? but what about jumps to labels. And it's no longer readable by humans.
-- vm: how to remove all unused subroutines? (in the assembly codegen, we let 64tass solve this for us)
+- vm: how to remove all unused subroutines? (in the 6502 assembly codegen, we let 64tass solve this for us)
 - vm: rather than being able to jump to any 'address' (IPTR), use 'blocks' that have entry and exit points -> even better dead code elimination possible too
 - vm: add more assignments to translateInplaceAssign()
 - Inliner: also inline function call expressions, and remove it from the StatementOptimizer
diff --git a/examples/test.p8 b/examples/test.p8
index 9f11c10cb..84fa138ee 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -17,19 +17,26 @@ other {
 
 main {
 
+    sub ands(ubyte arg, ubyte b1, ubyte b2, ubyte b3, ubyte b4) -> ubyte {
+        return arg>b1 and arg>b2 and arg>b3 and arg>b4
+    }
+
+    sub ors(ubyte arg, ubyte b1, ubyte b2, ubyte b3, ubyte b4) -> ubyte {
+        return arg==b1 or arg==b2 or arg==b3 or arg==b4
+    }
 
     sub start() {
-        ubyte @shared ix = other.getter()
-        ix = other.getter()
-        ix++
-        ix = other.getter()
-        ix++
-        ix = other.getter()
-        ix++
-        ix = other.getter()
-        ix++
-        ix = other.getter()
-        ix++
+        ubyte @shared a
+        ubyte @shared b
+
+        txt.print_ub(ands(10, 2,3,4,5))
+        txt.spc()
+        txt.print_ub(ands(10, 20,3,4,5))
+        txt.spc()
+        txt.print_ub(ors(10, 2,3,40,5))
+        txt.spc()
+        txt.print_ub(ors(10, 1,10,40,5))
+        txt.spc()
 
 ;        ; a "pixelshader":
 ;        sys.gfx_enable(0)       ; enable lo res screen
diff --git a/virtualmachine/src/prog8/vm/SysCalls.kt b/virtualmachine/src/prog8/vm/SysCalls.kt
index ecf73ab62..2f89091fe 100644
--- a/virtualmachine/src/prog8/vm/SysCalls.kt
+++ b/virtualmachine/src/prog8/vm/SysCalls.kt
@@ -1,6 +1,6 @@
 package prog8.vm
 
-import kotlin.math.*
+import kotlin.math.min
 
 /*
 SYSCALLS: