ir: fix handling of labeled chunks

codeGenIntermediate/src/prog8/codegen/intermediate/BuiltinFuncGen.kt

@@ -407,13 +407,12 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
     }
 
     private fun assignRegisterTo(target: PtExpression, register: Int): IRCodeChunks {
-        val code = IRCodeChunk(null, target.position)
         val assignment = PtAssignment(target.position)
         val assignTarget = PtAssignTarget(target.position)
         assignTarget.children.add(target)
         assignment.children.add(assignTarget)
         assignment.children.add(PtMachineRegister(register, target.type, target.position))
-        val result = mutableListOf<IRCodeChunkBase>(code)
+        val result = mutableListOf<IRCodeChunkBase>()
         result += codeGen.translateNode(assignment)
         return result
     }

codeGenIntermediate/src/prog8/codegen/intermediate/ExpressionGen.kt

@@ -56,8 +56,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 listOf(code)
             }
             is PtMemoryByte -> {
-                val code = IRCodeChunk(null, expr.position)
+                val result = mutableListOf<IRCodeChunkBase>()
-                val result = mutableListOf<IRCodeChunkBase>(code)
                 if(expr.address is PtNumber) {
                     val address = (expr.address as PtNumber).number.toInt()
                     addInstr(result, IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1=resultRegister, value = address), null, expr.position)

codeGenIntermediate/src/prog8/codegen/intermediate/IRCodeGen.kt

@@ -213,7 +213,7 @@ class IRCodeGen(
     }
 
     internal fun translateNode(node: PtNode): IRCodeChunks {
-        return when(node) {
+        val chunks = when(node) {
             is PtScopeVarsDecls -> emptyList() // vars should be looked up via symbol table
             is PtVariable -> emptyList() // var should be looked up via symbol table
             is PtMemMapped -> emptyList() // memmapped var should be looked up via symbol table
@@ -264,6 +264,14 @@ class IRCodeGen(
             is PtSub -> throw AssemblyError("nested subroutines should have been flattened ${node.position}")
             else -> TODO("missing codegen for $node")
         }
+
+        chunks.forEach { chunk ->
+            require(chunk.isNotEmpty() || chunk.label != null) {
+                "chunk should have instructions and/or a label"
+            }
+        }
+
+        return chunks
     }
 
     private fun translate(branch: PtConditionalBranch): IRCodeChunks {

codeGenIntermediate/src/prog8/codegen/intermediate/IRPeepholeOptimizer.kt

@@ -5,6 +5,7 @@ import prog8.intermediate.*
 internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
     fun optimize() {
         irprog.blocks.asSequence().flatMap { it.subroutines }.forEach { sub ->
+            removeEmptyChunks(sub)
             joinChunks(sub)
             sub.chunks.forEach { chunk ->
                 // we don't optimize Inline Asm chunks here.
@@ -27,6 +28,51 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         }
     }
 
+    private fun removeEmptyChunks(sub: IRSubroutine) {
+        if(sub.chunks.isEmpty())
+            return
+
+        /*
+        Empty Code chunk with label ->
+            If next chunk has no label -> move label to next chunk, remove original
+            If next chunk has label -> label name should be the same, remove original. Otherwise FOR NOW leave it in place. (TODO: consolidate labels into 1)
+        Empty Code chunk without label ->
+            should not have been generated! ERROR.
+         */
+
+
+        val relabelChunks = mutableListOf<Pair<Int, String>>()
+        val removeChunks = mutableListOf<Int>()
+
+        sub.chunks.withIndex().forEach { (index, chunk) ->
+            require(chunk.isNotEmpty() || chunk.label!=null) {
+                "chunk should have instructions and/or a label"
+            }
+
+            if(chunk is IRCodeChunk && chunk.label!=null && chunk.instructions.isEmpty()) {
+                val nextchunk = sub.chunks[index+1]
+                if(nextchunk.label==null) {
+                    // can transplant label to next chunk and remove this empty one.
+                    relabelChunks += Pair(index+1, chunk.label!!)
+                    removeChunks += index
+                 } else {
+                    if(chunk.label==nextchunk.label)
+                         removeChunks += index
+                    else {
+                        // TODO: consolidate labels on same chunk
+                    }
+                }
+            }
+        }
+
+        relabelChunks.forEach { (index, label) ->
+            val chunk = IRCodeChunk(label, sub.chunks[index].position)
+            chunk.instructions += sub.chunks[index].instructions
+            sub.chunks[index] = chunk
+        }
+        removeChunks.reversed().forEach { index -> sub.chunks.removeAt(index) }
+    }
+
     private fun joinChunks(sub: IRSubroutine) {
         /*
         Subroutine contains a list of chunks.
@@ -34,9 +80,10 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         TODO: this has to be changed later...
         */
 
-/*        if(sub.chunks.isEmpty())
+        if(sub.chunks.isEmpty())
             return
 
+/*
         fun mayJoin(previous: IRCodeChunkBase, chunk: IRCodeChunkBase): Boolean {
             if(previous is IRCodeChunk && chunk is IRCodeChunk) {
                 return true

docs/source/todo.rst

@@ -3,8 +3,9 @@ TODO
 
 For next release
 ^^^^^^^^^^^^^^^^
-- ir: get rid of IRCodeLabel, make every label start a new code chunk, give those a 'label' property.
 - ir: fix program to be list of chunks
+- ir: fix unit tests
+- ir: link all sequential chunks to another (exiting one chunk 'calls' the next chunk)
 - ir: jump/branch instructions don't link to a PC index anymore, but to the actual chunk with that label
 - ir: fix joinChunks() in the IR optimizer ? Fix TestIRPeepholeOptimizer and TestVm
 - vm: program is list of chunks, fix dispatcher

intermediate/src/prog8/intermediate/IRFileReader.kt

@@ -263,7 +263,7 @@ class IRFileReader {
         line = lines.next()
         var chunk = IRCodeChunk(null, Position.DUMMY)
         if(line=="<C>") {
-            chunk = parseCodeChunk(line, lines, null)!!
+            chunk = parseCodeChunk(line, lines)!!
             line = lines.next()
         }
         if(line!="</INITGLOBALS>")
@@ -285,8 +285,8 @@ class IRFileReader {
     }
 
     private val blockPattern = Regex("<BLOCK NAME=(.+) ADDRESS=(.+) ALIGN=(.+) POS=(.+)>")
-    private val inlineAsmPattern = Regex("<INLINEASM IR=(.+) POS=(.+)>")
+    private val inlineAsmPattern = Regex("<INLINEASM LABEL=(.*) IR=(.+) POS=(.+)>")
-    private val bytesPattern = Regex("<BYTES POS=(.+)>")
+    private val bytesPattern = Regex("<BYTES LABEL=(.*) POS=(.+)>")
     private val asmsubPattern = Regex("<ASMSUB NAME=(.+) ADDRESS=(.+) CLOBBERS=(.*) RETURNS=(.*) POS=(.+)>")
     private val subPattern = Regex("<SUB NAME=(.+) RETURNTYPE=(.+) POS=(.+)>")
     private val posPattern = Regex("\\[(.+): line (.+) col (.+)-(.+)\\]")
@@ -312,18 +312,19 @@ class IRFileReader {
                 val sub = parseAsmSubroutine(line, lines)
                 block += sub
             } else if(line.startsWith("<INLINEASM ")) {
-                val asm = parseInlineAssembly(line, lines, null)
+                val asm = parseInlineAssembly(line, lines)
                 block += asm
             } else
                 throw IRParseException("invalid line in BLOCK")
         }
     }
 
-    private fun parseInlineAssembly(startline: String, lines: Iterator<String>, label: String?): IRInlineAsmChunk {
+    private fun parseInlineAssembly(startline: String, lines: Iterator<String>): IRInlineAsmChunk {
-        // <INLINEASM IR=true POS=[examples/test.p8: line 8 col 6-9]>
+        // <INLINEASM LABEL=optional-label IR=true POS=[examples/test.p8: line 8 col 6-9]>
         val match = inlineAsmPattern.matchEntire(startline) ?: throw IRParseException("invalid INLINEASM")
-        val isIr = match.groupValues[1].toBoolean()
+        val label = match.groupValues[1]
-        val pos = parsePosition(match.groupValues[2])
+        val isIr = match.groupValues[2].toBoolean()
+        val pos = parsePosition(match.groupValues[3])
         val asmlines = mutableListOf<String>()
         var line = lines.next()
         while(line!="</INLINEASM>") {
@@ -352,7 +353,7 @@ class IRFileReader {
             params += Pair(dt, regsf)
         }
         line = lines.next()
-        val asm = parseInlineAssembly(line, lines, null)
+        val asm = parseInlineAssembly(line, lines)
         while(line!="</ASMSUB>")
             line = lines.next()
         val clobberRegs = if(clobbers.isBlank()) emptyList() else clobbers.split(',').map { CpuRegister.valueOf(it) }
@@ -386,12 +387,12 @@ class IRFileReader {
             val line = lines.next()
             if(line=="</SUB>")
                 return sub
-            val chunk = if(line=="<C>")
+            val chunk = if(line.startsWith("<C"))
-                parseCodeChunk(line, lines, null)
+                parseCodeChunk(line, lines)
             else if(line.startsWith("<BYTES "))
-                parseBinaryBytes(line, lines, null)
+                parseBinaryBytes(line, lines)
             else if(line.startsWith("<INLINEASM "))
-                parseInlineAssembly(line, lines, null)
+                parseInlineAssembly(line, lines)
             else
                 throw IRParseException("invalid sub child node")
 
@@ -406,9 +407,10 @@ class IRFileReader {
         return sub
     }
 
-    private fun parseBinaryBytes(startline: String, lines: Iterator<String>, label: String?): IRInlineBinaryChunk {
+    private fun parseBinaryBytes(startline: String, lines: Iterator<String>): IRInlineBinaryChunk {
         val match = bytesPattern.matchEntire(startline) ?: throw IRParseException("invalid BYTES")
-        val pos = parsePosition(match.groupValues[1])
+        val label = match.groupValues[1]
+        val pos = parsePosition(match.groupValues[2])
         val bytes = mutableListOf<UByte>()
         var line = lines.next()
         while(line!="</BYTES>") {
@@ -436,13 +438,17 @@ class IRFileReader {
         }
     }
 
-    private fun parseCodeChunk(firstline: String, lines: Iterator<String>, label: String?): IRCodeChunk? {
+    private fun parseCodeChunk(firstline: String, lines: Iterator<String>): IRCodeChunk? {
-        if(firstline!="<C>") {
+        if(!firstline.startsWith("<C")) {
             if(firstline=="</SUB>")
                 return null
             else
                 throw IRParseException("invalid or empty <C>ODE chunk")
         }
+        val label = if(firstline.startsWith("<C LABEL="))
+            firstline.split('=', limit = 2)[1].dropLast(1)
+        else
+            null
         val chunk = IRCodeChunk(label, Position.DUMMY)
         while(true) {
             val line = lines.next()

intermediate/src/prog8/intermediate/IRFileWriter.kt

@@ -64,12 +64,14 @@ class IRFileWriter(private val irProgram: IRProgram, outfileOverride: Path?) {
                         is IRInlineAsmChunk -> writeInlineAsm(chunk)
                         is IRInlineBinaryChunk -> writeInlineBytes(chunk)
                         else -> {
+                            if(chunk.label!=null)
+                                out.write("<C LABEL=${chunk.label}>\n")
+                            else
                                 out.write("<C>\n")
-                            if (chunk.instructions.isEmpty())
-                                throw InternalCompilerException("empty code chunk in ${it.name} ${it.position}")
                             chunk.instructions.forEach { instr ->
                                 numInstr++
                                 out.write(instr.toString())
+                                out.write("\n")
                             }
                             out.write("</C>\n")
                         }
@@ -100,7 +102,7 @@ class IRFileWriter(private val irProgram: IRProgram, outfileOverride: Path?) {
     }
 
     private fun writeInlineBytes(chunk: IRInlineBinaryChunk) {
-        out.write("<BYTES POS=${chunk.position}>\n")
+        out.write("<BYTES LABEL=${chunk.label ?: ""} POS=${chunk.position}>\n")
         chunk.data.withIndex().forEach {(index, byte) ->
             out.write(byte.toString(16).padStart(2,'0'))
             if(index and 63 == 63 && index < chunk.data.size-1)
@@ -110,7 +112,7 @@ class IRFileWriter(private val irProgram: IRProgram, outfileOverride: Path?) {
     }
 
     private fun writeInlineAsm(chunk: IRInlineAsmChunk) {
-        out.write("<INLINEASM IR=${chunk.isIR} POS=${chunk.position}>\n")
+        out.write("<INLINEASM LABEL=${chunk.label ?: ""} IR=${chunk.isIR} POS=${chunk.position}>\n")
         out.write(chunk.assembly)
         out.write("\n</INLINEASM>\n")
     }

intermediate/src/prog8/intermediate/IRProgram.kt

@@ -72,7 +72,8 @@ class IRProgram(val name: String,
             }
             it.subroutines.forEach { sub ->
                 sub.chunks.forEach { chunk ->
-                    if (chunk is IRInlineAsmChunk) { require(chunk.instructions.isEmpty()) }
+                    if (chunk is IRCodeChunk) require(chunk.instructions.isNotEmpty() || chunk.label!=null)
+                    else require(chunk.instructions.isEmpty())
                 }
             }
         }
@@ -143,7 +144,12 @@ class IRSubroutine(val name: String,
         require(returnType==null || returnType in NumericDatatypes) {"non-numeric returntype $returnType"}
     }
 
-    operator fun plusAssign(chunk: IRCodeChunkBase) { chunks+= chunk }
+    operator fun plusAssign(chunk: IRCodeChunkBase) {
+        require(chunk.isNotEmpty() || chunk.label!=null) {
+            "chunk should have instructions and/or a label"
+        }
+        chunks+= chunk
+    }
 }
 
 class IRAsmSubroutine(