asmsub stack arg

compiler/src/prog8/ast/processing/AstChecker.kt

@@ -317,14 +317,11 @@ internal class AstChecker(private val program: Program,
                 err("carry parameter has to come last")
 
         } else {
-            // TODO: non-asm subroutines can only take numeric arguments for now. (not strings and arrays) Maybe this can be improved now that we have '&' ?
-            // the way string params are treated is almost okay (their address is passed) but the receiving subroutine treats it as an integer rather than referring back to the original string.
-            // the way array params are treated is buggy; it thinks the subroutine needs a byte parameter in place of a byte[] ...
-            // This is not easy to fix because strings and arrays are treated a bit simplistic (a "virtual" pointer to the value on the heap)
-            // while passing them as subroutine parameters would require a "real" pointer OR copying the VALUE to the subroutine's parameter variable (which is very inefficient).
-            // For now, don't pass strings and arrays as parameters and instead create the workaround as suggested in the error message below.
-            if(!subroutine.parameters.all{it.type in NumericDatatypes }) {
-                err("Non-asm subroutine can only take numerical parameters (no str/array types) for now. Workaround (for nested subroutine): access the variable from the outer scope directly.")
+            // Pass-by-reference datatypes can not occur as parameters to a subroutine directly
+            // Instead, their reference (address) should be passed (as an UWORD).
+            // The language has no typed pointers at this time.
+            if(subroutine.parameters.any{it.type in PassByReferenceDatatypes }) {
+                err("Pass-by-reference types (str, array) cannot occur as a parameter type directly. Instead, use an uword for their address, or access the variable from the outer scope directly.")
             }
         }
     }

compiler/src/prog8/ast/processing/StatementReorderer.kt

@@ -319,7 +319,7 @@ internal class StatementReorderer(private val program: Program): IAstModifyingVi
                 }
             }
             null -> {}
-            else -> TODO("call to something weird $sub   ${call.target}")
+            else -> throw FatalAstException("call to something weird $sub   ${call.target}")
         }
     }
 

compiler/src/prog8/compiler/target/c64/codegen2/AsmGen2.kt

@@ -662,35 +662,35 @@ internal class AsmGen2(val program: Program,
             out("  ldx  c64.SCRATCH_ZPREGX")        // restore X again
     }
 
-    fun translateSubroutineArgument(arg: IndexedValue<SubroutineParameter>, value: Expression, sub: Subroutine) {
+    fun translateSubroutineArgument(parameter: IndexedValue<SubroutineParameter>, value: Expression, sub: Subroutine) {
         val sourceDt = value.inferType(program)!!
-        if(!argumentTypeCompatible(sourceDt, arg.value.type))
+        if(!argumentTypeCompatible(sourceDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
         if(sub.asmParameterRegisters.isEmpty()) {
-            // pass arg via a variable
-            val paramVar = arg.value
+            // pass parameter via a variable
+            val paramVar = parameter.value
             val scopedParamVar = (sub.scopedname+"."+paramVar.name).split(".")
             val target = AssignTarget(null, IdentifierReference(scopedParamVar, sub.position), null, null, sub.position)
             target.linkParents(value.parent)
             when (value) {
                 is NumericLiteralValue -> {
                     // optimize when the argument is a constant literal
-                    when(arg.value.type) {
+                    when(parameter.value.type) {
                         in ByteDatatypes -> assignFromByteConstant(target, value.number.toShort())
                         in WordDatatypes -> assignFromWordConstant(target, value.number.toInt())
                         DataType.FLOAT -> assignFromFloatConstant(target, value.number.toDouble())
                         in PassByReferenceDatatypes -> throw AssemblyError("can't pass string/array as arguments?")
-                        else -> throw AssemblyError("weird arg datatype")
+                        else -> throw AssemblyError("weird parameter datatype")
                     }
                 }
                 is IdentifierReference -> {
                     // optimize when the argument is a variable
-                    when (arg.value.type) {
+                    when (parameter.value.type) {
                         in ByteDatatypes -> assignFromByteVariable(target, value)
                         in WordDatatypes -> assignFromWordVariable(target, value)
                         DataType.FLOAT -> assignFromFloatVariable(target, value)
                         in PassByReferenceDatatypes -> throw AssemblyError("can't pass string/array as arguments?")
-                        else -> throw AssemblyError("weird arg datatype")
+                        else -> throw AssemblyError("weird parameter datatype")
                     }
                 }
                 is RegisterExpr -> {
@@ -718,13 +718,17 @@ internal class AsmGen2(val program: Program,
                 }
             }
         } else {
-            // pass arg via a register parameter
-            val paramRegister = sub.asmParameterRegisters[arg.index]
+            // pass parameter via a register parameter
+            val paramRegister = sub.asmParameterRegisters[parameter.index]
             val statusflag = paramRegister.statusflag
             val register = paramRegister.registerOrPair
             val stack = paramRegister.stack
             when {
-                stack==true -> TODO("param on stack")
+                stack -> {
+                    // push arg onto the stack
+                    // note: argument order is reversed (first argument will be deepest on the stack)
+                    translateExpression(value)
+                }
                 statusflag!=null -> {
                     if (statusflag == Statusflag.Pc) {
                         // this param needs to be set last, right before the jsr

compiler/src/prog8/compiler/target/c64/codegen2/AsmOptimizer.kt

@@ -54,7 +54,7 @@ fun optimizeAssembly(lines: MutableList<String>): Int {
         numberOfOptimizations++
     }
 
-    // TODO more assembly optimizations?
+    // TODO more assembly optimizations
 
     return numberOfOptimizations
 }
@@ -101,7 +101,7 @@ fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>):
 
     // optimize sequential assignments of the isSameAs value to various targets (bytes, words, floats)
     // the float one is the one that requires 2*7=14 lines of code to check...
-    // @todo a better place to do this is in the Compiler instead and work on opcodes, and never even create the inefficient asm...
+    // @todo a better place to do this is in the Compiler instead and transform the Ast, and never even create the inefficient asm in the first place...
 
     val removeLines = mutableListOf<Int>()
     for (pair in linesByFourteen) {

compiler/src/prog8/optimizer/StatementOptimizer.kt

@@ -107,13 +107,6 @@ internal class StatementOptimizer(private val program: Program) : IAstModifyingV
         if(subroutine.canBeAsmSubroutine) {
             optimizationsDone++
             return subroutine.intoAsmSubroutine()   // TODO this doesn't work yet due to parameter vardecl issue
-
-            // TODO fix parameter passing so this also works:
-//            asmsub aa(byte arg @ Y) -> clobbers() -> () {
-//                byte local = arg            ; @todo fix 'undefined symbol arg' by some sort of alias name for the parameter
-//                A=44
-//            }
-
         }
 
         if(subroutine !in callgraph.usedSymbols && !forceOutput) {

docs/source/todo.rst

@@ -19,6 +19,15 @@ these should call optimized pieces of assembly code, so they run as fast as poss
 
 For now, we have the ``memcopy``, ``memset`` and ``strlen`` builtin functions.
 
+Fixes
+^^^^^
+
+fix asmsub parameters so this works::
+
+      asmsub aa(byte arg @ Y) -> clobbers() -> () {
+          byte local = arg      ; @todo fix 'undefined symbol arg' that occurs here
+          A=44
+      }
 
 
 More optimizations

examples/test.p8

@@ -4,25 +4,14 @@
 main {
 
     sub start() {
-        derp.dop()
-
-        A=derp.dop.zzz
-
-        derp.dop.zzz=3
-
-
-        uword addr = &derp.dop.name         ; @todo strange error "pointer-of operand must be the name of a heap variable"
-        c64scr.print(&derp.dop.name)
+        A = testsub(33)
     }
-}
 
-
-derp {
-
-    sub dop() {
-        ubyte zzz=33
-        str name="irmen"
-
-        A=54
+    asmsub testsub(ubyte foo @stack) -> ubyte @stack {
+        %asm {{
+            Y=44
+            rts
+        }}
     }
+
 }