diff --git a/src/main/fragment/mos6502-common/vdum1_lt_vdum2_then_la1.asm b/src/main/fragment/mos6502-common/vdum1_lt_vdum2_then_la1.asm
new file mode 100644
index 000000000..8b8a09932
--- /dev/null
+++ b/src/main/fragment/mos6502-common/vdum1_lt_vdum2_then_la1.asm
@@ -0,0 +1,16 @@
+lda {m1}+3
+cmp {m2}+3
+bcc {la1}
+bne !+
+lda {m1}+2
+cmp {m2}+2
+bcc {la1}
+bne !+
+lda {m1}+1
+cmp {m2}+1
+bcc {la1}
+bne !+
+lda {m1}
+cmp {m2}
+bcc {la1}
+!:
diff --git a/src/main/java/dk/camelot64/kickc/asm/AsmChunk.java b/src/main/java/dk/camelot64/kickc/asm/AsmChunk.java
index 31cf452c5..d73d71e6e 100644
--- a/src/main/java/dk/camelot64/kickc/asm/AsmChunk.java
+++ b/src/main/java/dk/camelot64/kickc/asm/AsmChunk.java
@@ -42,11 +42,13 @@ public class AsmChunk {
     */
    private String fragment;
 
-   /** If the chunk represents a PHI transition (See. {@link PhiTransitions}) this contains the transition ID. */
-   private String phiTransitionId;
+   /** If the chunk is part of a complex statement this is the sub-ID used for identifying the part of the statement represented.
+    * For PHI transitions (See. {@link PhiTransitions}) this contains the transition ID. For call prepare this holds the parameter. */
+   private String subStatementId;
 
-   /** If the chunk is an assignment in a PHI transition this contains the index of the assignment within the transition. */
-   private Integer phiTransitionAssignmentIdx;
+   /** If the chunk is part of a complex statement this is the sub index used for identifying the part of the statement represented.
+   * For  PHI transitions this contains the index of the assignment within the transition. For call prepares this is the index of the parameter. */
+   private Integer subStatementIdx;
 
    /** The full name of the containing scope (procedure). */
    private String scopeLabel;
@@ -112,20 +114,20 @@ public class AsmChunk {
       this.fragment = fragment;
    }
 
-   public String getPhiTransitionId() {
-      return phiTransitionId;
+   public String getSubStatementId() {
+      return subStatementId;
    }
 
-   public void setPhiTransitionId(String phiTransitionId) {
-      this.phiTransitionId = phiTransitionId;
+   public void setSubStatementId(String subStatementId) {
+      this.subStatementId = subStatementId;
    }
 
-   public Integer getPhiTransitionAssignmentIdx() {
-      return phiTransitionAssignmentIdx;
+   public Integer getSubStatementIdx() {
+      return subStatementIdx;
    }
 
-   public void setPhiTransitionAssignmentIdx(Integer phiTransitionAssignmentIdx) {
-      this.phiTransitionAssignmentIdx = phiTransitionAssignmentIdx;
+   public void setSubStatementIdx(Integer subStatementIdx) {
+      this.subStatementIdx = subStatementIdx;
    }
 
    public String getScopeLabel() {
@@ -252,10 +254,10 @@ public class AsmChunk {
          if(source != null) {
             out.append(" ").append(source.replace('\r', ' ').replace('\n', ' '));
          }
-         if(phiTransitionId != null) {
-            out.append(" [").append(phiTransitionId);
-            if(phiTransitionAssignmentIdx != null) {
-               out.append("#").append(phiTransitionAssignmentIdx);
+         if(subStatementId != null) {
+            out.append(" [").append(subStatementId);
+            if(subStatementIdx != null) {
+               out.append("#").append(subStatementIdx);
             }
             out.append("]");
          }
diff --git a/src/main/java/dk/camelot64/kickc/passes/Pass4AssertNoCpuClobber.java b/src/main/java/dk/camelot64/kickc/passes/Pass4AssertNoCpuClobber.java
index 38a343c5d..b9470e4ab 100644
--- a/src/main/java/dk/camelot64/kickc/passes/Pass4AssertNoCpuClobber.java
+++ b/src/main/java/dk/camelot64/kickc/passes/Pass4AssertNoCpuClobber.java
@@ -5,6 +5,8 @@ import dk.camelot64.kickc.asm.AsmClobber;
 import dk.camelot64.kickc.asm.AsmProgram;
 import dk.camelot64.kickc.model.*;
 import dk.camelot64.kickc.model.statements.Statement;
+import dk.camelot64.kickc.model.statements.StatementCallPrepare;
+import dk.camelot64.kickc.model.statements.StatementPhiBlock;
 import dk.camelot64.kickc.model.symbols.Variable;
 import dk.camelot64.kickc.model.values.LabelRef;
 import dk.camelot64.kickc.model.values.RValue;
@@ -73,10 +75,11 @@ public class Pass4AssertNoCpuClobber extends Pass2Base {
 
             // Find alive variables
             List<VariableRef> aliveVars = new ArrayList<>(getProgram().getLiveRangeVariablesEffective().getAliveEffective(statement));
+
             // If the chunk is an assignment in a phi transition, examine the later phi transition assignments and update alive variables alive and variables assigned
-            if(asmChunk.getPhiTransitionId() != null && asmChunk.getPhiTransitionAssignmentIdx() != null) {
-               String phiTransitionId = asmChunk.getPhiTransitionId();
-               int transitionAssignmentIdx = asmChunk.getPhiTransitionAssignmentIdx();
+            if(statement instanceof StatementPhiBlock && asmChunk.getSubStatementId() != null && asmChunk.getSubStatementIdx() != null) {
+               String phiTransitionId = asmChunk.getSubStatementId();
+               int transitionAssignmentIdx = asmChunk.getSubStatementIdx();
                ControlFlowBlock statementBlock = getProgram().getStatementInfos().getBlock(statementIdx);
                Map<LabelRef, PhiTransitions> programPhiTransitions = getProgram().getPhiTransitions();
                PhiTransitions phiTransitions = programPhiTransitions.get(statementBlock.getLabel());
@@ -98,6 +101,21 @@ public class Pass4AssertNoCpuClobber extends Pass2Base {
                }
             }
 
+            // If the chunk is an call parameter prepare, examine the later call parameter prepares and update alive variables 
+            if(statement instanceof StatementCallPrepare && asmChunk.getSubStatementId() != null && asmChunk.getSubStatementIdx() != null) {
+               int transitionAssignmentIdx = asmChunk.getSubStatementIdx();
+               final StatementCallPrepare callPrepare = (StatementCallPrepare) statement;
+               final int numParameters = callPrepare.getNumParameters();
+               for(int idx = 0; idx < numParameters; idx++) {
+                  final RValue parameter = callPrepare.getParameter(idx);
+                  if(idx > transitionAssignmentIdx) {
+                     // If the parameter prepare is later than the current one
+                     Collection<VariableRef> alive = VariableReferenceInfos.getReferencedVars(parameter);
+                     aliveVars.addAll(alive);
+                  }
+               }
+            }
+
             // Non-assigned alive variables must not be clobbered
             for(VariableRef aliveVar : aliveVars) {
                Variable variable = getProgram().getSymbolInfos().getVariable(aliveVar);
@@ -115,7 +133,7 @@ public class Pass4AssertNoCpuClobber extends Pass2Base {
                   if(verbose) {
                      throw new CompileError(
                            "Error! Generated ASM has register clobber problem. " +
-                                 "Alive variable "+aliveVar + " register " + aliveVarRegister + " clobbered by the ASM generated by statement "+statement.toString(getProgram(), true),
+                                 "Alive variable " + aliveVar + " register " + aliveVarRegister + " clobbered by the ASM generated by statement " + statement.toString(getProgram(), true),
                            statement.getSource()
                      );
                   }
diff --git a/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java b/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java
index de91c502b..2dea37fb3 100644
--- a/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java
+++ b/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java
@@ -280,7 +280,7 @@ public class Pass4CodeGeneration {
             signature.append("zp(").append(AsmFormat.getAsmNumber(registerZp.getZp())).append(")");
          } else if(allocation instanceof Registers.RegisterMainMem) {
             Registers.RegisterMainMem registerMainMem = (Registers.RegisterMainMem) allocation;
-            signature.append("mem(").append(registerMainMem.getAddress()==null?"":AsmFormat.getAsmNumber(registerMainMem.getAddress())).append(")");
+            signature.append("mem(").append(registerMainMem.getAddress() == null ? "" : AsmFormat.getAsmNumber(registerMainMem.getAddress())).append(")");
          } else if(allocation instanceof Registers.RegisterAByte) {
             signature.append("register(A)");
          } else if(allocation instanceof Registers.RegisterXByte) {
@@ -850,26 +850,29 @@ public class Pass4CodeGeneration {
                List<RValue> callParameters = call.getParameters();
                List<Variable> procParameters = procedure.getParameters();
                for(int i = 0; i < procParameters.size(); i++) {
+                  if(i > 0)
+                     asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   Variable procParameter = procParameters.get(i);
                   RValue callParameter = callParameters.get(i);
                   SymbolType parameterType = procParameter.getType();
                   AsmFragmentInstanceSpecFactory asmFragmentInstanceSpecFactory = new AsmFragmentInstanceSpecFactory(new StackPushValue(parameterType), callParameter, program, block.getScope());
-                  asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   ensureEncoding(asm, asmFragmentInstanceSpecFactory);
                   generateAsm(asm, asmFragmentInstanceSpecFactory.getAsmFragmentInstanceSpec());
+                  asm.getCurrentChunk().setSubStatementIdx(i);
+                  asm.getCurrentChunk().setSubStatementId(procParameter.toString(program));
                }
                // Push additional bytes if needed
                long stackFrameByteSize = CallingConventionStack.getStackFrameByteSize(procedure);
                long parametersByteSize = CallingConventionStack.getParametersByteSize(procedure);
                if(stackFrameByteSize > parametersByteSize) {
+                  if(procParameters.size() > 0)
+                     asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   // Add padding to the stack to make room for the return value
                   String pushSignature = "_stackpushbyte_" + (stackFrameByteSize - parametersByteSize);
                   AsmFragmentInstanceSpec pushFragmentInstanceSpec = new AsmFragmentInstanceSpec(program, pushSignature, new LinkedHashMap<>(), block.getScope());
-                  asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   generateAsm(asm, pushFragmentInstanceSpec);
 
                }
-               asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
             }
          } else if(statement instanceof StatementCallExecute) {
             StatementCallExecute call = (StatementCallExecute) statement;
@@ -882,26 +885,24 @@ public class Pass4CodeGeneration {
             StatementCallFinalize call = (StatementCallFinalize) statement;
             Procedure procedure = getScope().getProcedure(call.getProcedure());
             if(Procedure.CallingConvention.STACK_CALL.equals(procedure.getCallingConvention())) {
-
                long stackFrameByteSize = CallingConventionStack.getStackFrameByteSize(procedure);
                long returnByteSize = procedure.getReturnType() == null ? 0 : procedure.getReturnType().getSizeBytes();
-               if(stackFrameByteSize > returnByteSize) {
+               long stackCleanBytes = (call.getlValue() == null) ? stackFrameByteSize : (stackFrameByteSize - returnByteSize);
+               if(stackCleanBytes > 0) {
                   // Clean up the stack
-                  String pullSignature = "_stackpullbyte_" + (stackFrameByteSize - returnByteSize);
+                  String pullSignature = "_stackpullbyte_" + stackCleanBytes;
                   AsmFragmentInstanceSpec pullFragmentInstanceSpec = new AsmFragmentInstanceSpec(program, pullSignature, new LinkedHashMap<>(), block.getScope());
-                  asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   generateAsm(asm, pullFragmentInstanceSpec);
                }
-
                // Pull result from the stack
                if(call.getlValue() != null) {
+                  if(stackCleanBytes>0)
+                     asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   SymbolType returnType = procedure.getReturnType();
                   AsmFragmentInstanceSpecFactory asmFragmentInstanceSpecFactory = new AsmFragmentInstanceSpecFactory(call.getlValue(), new StackPullValue(returnType), program, block.getScope());
-                  asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(program, verboseAliveInfo));
                   ensureEncoding(asm, asmFragmentInstanceSpecFactory);
                   generateAsm(asm, asmFragmentInstanceSpecFactory.getAsmFragmentInstanceSpec());
                }
-
             }
          } else if(statement instanceof StatementReturn) {
             Procedure procedure = null;
@@ -1173,7 +1174,7 @@ public class Pass4CodeGeneration {
          }
          chunkSrc += "to " + toBlock.getLabel().getFullName();
          asm.startChunk(scope, toFirstStatement.getIndex(), chunkSrc);
-         asm.getCurrentChunk().setPhiTransitionId(transition.getTransitionId());
+         asm.getCurrentChunk().setSubStatementId(transition.getTransitionId());
          for(ControlFlowBlock fBlock : transition.getFromBlocks()) {
             asm.addLabel(AsmFormat.asmFix(toBlock.getLabel().getLocalName() + "_from_" + fBlock.getLabel().getLocalName()));
          }
@@ -1184,8 +1185,8 @@ public class Pass4CodeGeneration {
             Statement statement = assignment.getPhiBlock();
             // Generate an ASM move fragment
             asm.startChunk(scope, statement.getIndex(), "[" + statement.getIndex() + "] phi " + lValue.toString(program) + " = " + rValue.toString(program));
-            asm.getCurrentChunk().setPhiTransitionId(transition.getTransitionId());
-            asm.getCurrentChunk().setPhiTransitionAssignmentIdx(assignment.getAssignmentIdx());
+            asm.getCurrentChunk().setSubStatementId(transition.getTransitionId());
+            asm.getCurrentChunk().setSubStatementIdx(assignment.getAssignmentIdx());
             if(isRegisterCopy(lValue, rValue)) {
                asm.getCurrentChunk().setFragment("register_copy");
             } else {
diff --git a/src/test/ref/procedure-callingconvention-stack-0.log b/src/test/ref/procedure-callingconvention-stack-0.log
index e9ce5d9db..ac3d5e833 100644
--- a/src/test/ref/procedure-callingconvention-stack-0.log
+++ b/src/test/ref/procedure-callingconvention-stack-0.log
@@ -177,17 +177,14 @@ __bend:
   // main
 main: {
     .label __0 = 2
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::b#1] -- _stackpushbyte_=vbuc1 
     lda #7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (byte~) main::$0 ← callfinalize plus 
     // [7] (byte~) main::$0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [7] (byte~) main::$0 ← callfinalize plus  -- vbuz1=_stackpullbyte_ 
@@ -296,17 +293,14 @@ __bend_from___b1:
 __bend:
   // main
 main: {
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::b#1] -- _stackpushbyte_=vbuc1 
     lda #7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (byte~) main::$0 ← callfinalize plus 
     // [7] (byte~) main::$0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [7] (byte~) main::$0 ← callfinalize plus  -- vbuaa=_stackpullbyte_ 
@@ -418,17 +412,14 @@ Score: 67
   // main
 main: {
     // plus('0', 7)
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::b#1] -- _stackpushbyte_=vbuc1 
     lda #7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (byte~) main::$0 ← callfinalize plus 
     // [7] (byte~) main::$0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [7] (byte~) main::$0 ← callfinalize plus  -- vbuaa=_stackpullbyte_ 
diff --git a/src/test/ref/procedure-callingconvention-stack-1.log b/src/test/ref/procedure-callingconvention-stack-1.log
index e9ce5d9db..ac3d5e833 100644
--- a/src/test/ref/procedure-callingconvention-stack-1.log
+++ b/src/test/ref/procedure-callingconvention-stack-1.log
@@ -177,17 +177,14 @@ __bend:
   // main
 main: {
     .label __0 = 2
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::b#1] -- _stackpushbyte_=vbuc1 
     lda #7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (byte~) main::$0 ← callfinalize plus 
     // [7] (byte~) main::$0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [7] (byte~) main::$0 ← callfinalize plus  -- vbuz1=_stackpullbyte_ 
@@ -296,17 +293,14 @@ __bend_from___b1:
 __bend:
   // main
 main: {
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::b#1] -- _stackpushbyte_=vbuc1 
     lda #7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (byte~) main::$0 ← callfinalize plus 
     // [7] (byte~) main::$0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [7] (byte~) main::$0 ← callfinalize plus  -- vbuaa=_stackpullbyte_ 
@@ -418,17 +412,14 @@ Score: 67
   // main
 main: {
     // plus('0', 7)
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushbyte_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(byte) plus::b#1] -- _stackpushbyte_=vbuc1 
     lda #7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (byte~) main::$0 ← callfinalize plus 
     // [7] (byte~) main::$0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [7] (byte~) main::$0 ← callfinalize plus  -- vbuaa=_stackpullbyte_ 
diff --git a/src/test/ref/procedure-callingconvention-stack-2.log b/src/test/ref/procedure-callingconvention-stack-2.log
index ae87a0b51..e566d81a9 100644
--- a/src/test/ref/procedure-callingconvention-stack-2.log
+++ b/src/test/ref/procedure-callingconvention-stack-2.log
@@ -195,21 +195,18 @@ __bend:
   // main
 main: {
     .label __0 = 2
-    // [5] callprepare plus (word) $1234 (word) $2345 
-    // [5] callprepare plus (word) $1234 (word) $2345  -- _stackpushword_=vwuc1 
+    // [5] callprepare plus (word) $1234 (word) $2345  [(word) plus::a#0] -- _stackpushword_=vwuc1 
     lda #>$1234
     pha
     lda #<$1234
     pha
-    // [5] callprepare plus (word) $1234 (word) $2345  -- _stackpushword_=vwuc1 
+    // [5] callprepare plus (word) $1234 (word) $2345  [(word) plus::b#1] -- _stackpushword_=vwuc1 
     lda #>$2345
     pha
     lda #<$2345
     pha
-    // [5] callprepare plus (word) $1234 (word) $2345 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (word~) main::$0 ← callfinalize plus 
     // [7] (word~) main::$0 ← callfinalize plus  -- _stackpullbyte_2 
     pla
     pla
@@ -327,21 +324,18 @@ __bend:
   // main
 main: {
     .label __0 = 2
-    // [5] callprepare plus (word) $1234 (word) $2345 
-    // [5] callprepare plus (word) $1234 (word) $2345  -- _stackpushword_=vwuc1 
+    // [5] callprepare plus (word) $1234 (word) $2345  [(word) plus::a#0] -- _stackpushword_=vwuc1 
     lda #>$1234
     pha
     lda #<$1234
     pha
-    // [5] callprepare plus (word) $1234 (word) $2345  -- _stackpushword_=vwuc1 
+    // [5] callprepare plus (word) $1234 (word) $2345  [(word) plus::b#1] -- _stackpushword_=vwuc1 
     lda #>$2345
     pha
     lda #<$2345
     pha
-    // [5] callprepare plus (word) $1234 (word) $2345 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (word~) main::$0 ← callfinalize plus 
     // [7] (word~) main::$0 ← callfinalize plus  -- _stackpullbyte_2 
     pla
     pla
@@ -474,21 +468,18 @@ Score: 146
 main: {
     .label __0 = 2
     // plus(0x1234, 0x2345)
-    // [5] callprepare plus (word) $1234 (word) $2345 
-    // [5] callprepare plus (word) $1234 (word) $2345  -- _stackpushword_=vwuc1 
+    // [5] callprepare plus (word) $1234 (word) $2345  [(word) plus::a#0] -- _stackpushword_=vwuc1 
     lda #>$1234
     pha
     lda #<$1234
     pha
-    // [5] callprepare plus (word) $1234 (word) $2345  -- _stackpushword_=vwuc1 
+    // [5] callprepare plus (word) $1234 (word) $2345  [(word) plus::b#1] -- _stackpushword_=vwuc1 
     lda #>$2345
     pha
     lda #<$2345
     pha
-    // [5] callprepare plus (word) $1234 (word) $2345 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (word~) main::$0 ← callfinalize plus 
     // [7] (word~) main::$0 ← callfinalize plus  -- _stackpullbyte_2 
     pla
     pla
diff --git a/src/test/ref/procedure-callingconvention-stack-3.log b/src/test/ref/procedure-callingconvention-stack-3.log
index c91422f66..9d08be1a5 100644
--- a/src/test/ref/procedure-callingconvention-stack-3.log
+++ b/src/test/ref/procedure-callingconvention-stack-3.log
@@ -195,21 +195,18 @@ __bend:
   // main
 main: {
     .label __0 = 2
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushword_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(word) plus::a#0] -- _stackpushword_=vbuc1 
     lda #0
     pha
     lda #<'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushword_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(word) plus::b#1] -- _stackpushword_=vbuc1 
     lda #0
     pha
     lda #<7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (word~) main::$0 ← callfinalize plus 
     // [7] (word~) main::$0 ← callfinalize plus  -- _stackpullbyte_2 
     pla
     pla
@@ -330,21 +327,18 @@ __bend:
   // main
 main: {
     .label __0 = 2
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushword_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(word) plus::a#0] -- _stackpushword_=vbuc1 
     lda #0
     pha
     lda #<'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushword_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(word) plus::b#1] -- _stackpushword_=vbuc1 
     lda #0
     pha
     lda #<7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (word~) main::$0 ← callfinalize plus 
     // [7] (word~) main::$0 ← callfinalize plus  -- _stackpullbyte_2 
     pla
     pla
@@ -480,21 +474,18 @@ Score: 146
 main: {
     .label __0 = 2
     // plus('0', 7)
-    // [5] callprepare plus (byte) '0' (byte) 7 
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushword_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(word) plus::a#0] -- _stackpushword_=vbuc1 
     lda #0
     pha
     lda #<'0'
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7  -- _stackpushword_=vbuc1 
+    // [5] callprepare plus (byte) '0' (byte) 7  [(word) plus::b#1] -- _stackpushword_=vbuc1 
     lda #0
     pha
     lda #<7
     pha
-    // [5] callprepare plus (byte) '0' (byte) 7 
     // [6] callexecute plus  -- jsr 
     jsr plus
-    // [7] (word~) main::$0 ← callfinalize plus 
     // [7] (word~) main::$0 ← callfinalize plus  -- _stackpullbyte_2 
     pla
     pla
diff --git a/src/test/ref/procedure-callingconvention-stack-4.log b/src/test/ref/procedure-callingconvention-stack-4.log
index e78c1f3fc..5e414c40e 100644
--- a/src/test/ref/procedure-callingconvention-stack-4.log
+++ b/src/test/ref/procedure-callingconvention-stack-4.log
@@ -298,17 +298,14 @@ main: {
     ldy.z a
     iny
     sty.z v
-    // [7] callprepare plus (byte) '0' (byte) main::v#0 
-    // [7] callprepare plus (byte) '0' (byte) main::v#0  -- _stackpushbyte_=vbuc1 
+    // [7] callprepare plus (byte) '0' (byte) main::v#0  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [7] callprepare plus (byte) '0' (byte) main::v#0  -- _stackpushbyte_=vbuz1 
+    // [7] callprepare plus (byte) '0' (byte) main::v#0  [(byte) plus::b#1] -- _stackpushbyte_=vbuz1 
     lda.z v
     pha
-    // [7] callprepare plus (byte) '0' (byte) main::v#0 
     // [8] callexecute plus  -- jsr 
     jsr plus
-    // [9] (byte) main::w#0 ← callfinalize plus 
     // [9] (byte) main::w#0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [9] (byte) main::w#0 ← callfinalize plus  -- vbuz1=_stackpullbyte_ 
@@ -452,17 +449,14 @@ main: {
     tya
     tax
     inx
-    // [7] callprepare plus (byte) '0' (byte) main::v#0 
-    // [7] callprepare plus (byte) '0' (byte) main::v#0  -- _stackpushbyte_=vbuc1 
+    // [7] callprepare plus (byte) '0' (byte) main::v#0  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [7] callprepare plus (byte) '0' (byte) main::v#0  -- _stackpushbyte_=vbuxx 
+    // [7] callprepare plus (byte) '0' (byte) main::v#0  [(byte) plus::b#1] -- _stackpushbyte_=vbuxx 
     txa
     pha
-    // [7] callprepare plus (byte) '0' (byte) main::v#0 
     // [8] callexecute plus  -- jsr 
     jsr plus
-    // [9] (byte) main::w#0 ← callfinalize plus 
     // [9] (byte) main::w#0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [9] (byte) main::w#0 ← callfinalize plus  -- vbuaa=_stackpullbyte_ 
@@ -614,17 +608,14 @@ main: {
     tax
     inx
     // w = plus('0', v)
-    // [7] callprepare plus (byte) '0' (byte) main::v#0 
-    // [7] callprepare plus (byte) '0' (byte) main::v#0  -- _stackpushbyte_=vbuc1 
+    // [7] callprepare plus (byte) '0' (byte) main::v#0  [(byte) plus::a#0] -- _stackpushbyte_=vbuc1 
     lda #'0'
     pha
-    // [7] callprepare plus (byte) '0' (byte) main::v#0  -- _stackpushbyte_=vbuxx 
+    // [7] callprepare plus (byte) '0' (byte) main::v#0  [(byte) plus::b#1] -- _stackpushbyte_=vbuxx 
     txa
     pha
-    // [7] callprepare plus (byte) '0' (byte) main::v#0 
     // [8] callexecute plus  -- jsr 
     jsr plus
-    // [9] (byte) main::w#0 ← callfinalize plus 
     // [9] (byte) main::w#0 ← callfinalize plus  -- _stackpullbyte_1 
     pla
     // [9] (byte) main::w#0 ← callfinalize plus  -- vbuaa=_stackpullbyte_ 
diff --git a/src/test/ref/procedure-callingconvention-stack-5.log b/src/test/ref/procedure-callingconvention-stack-5.log
index ccffe5550..7cab745e3 100644
--- a/src/test/ref/procedure-callingconvention-stack-5.log
+++ b/src/test/ref/procedure-callingconvention-stack-5.log
@@ -234,14 +234,11 @@ __bend:
 main: {
     .label __0 = 4
     .label __1 = 6
-    // [5] callprepare next 
     // [5] callprepare next  -- _stackpushbyte_2 
     pha
     pha
-    // [5] callprepare next 
     // [6] callexecute next  -- jsr 
     jsr next
-    // [7] (signed word~) main::$0 ← callfinalize next 
     // [7] (signed word~) main::$0 ← callfinalize next  -- vwsz1=_stackpullsword_ 
     pla
     sta.z __0
@@ -252,14 +249,11 @@ main: {
     sta SCREEN
     lda.z __0+1
     sta SCREEN+1
-    // [9] callprepare next 
     // [9] callprepare next  -- _stackpushbyte_2 
     pha
     pha
-    // [9] callprepare next 
     // [10] callexecute next  -- jsr 
     jsr next
-    // [11] (signed word~) main::$1 ← callfinalize next 
     // [11] (signed word~) main::$1 ← callfinalize next  -- vwsz1=_stackpullsword_ 
     pla
     sta.z __1
@@ -357,14 +351,11 @@ __bend:
 main: {
     .label __0 = 2
     .label __1 = 4
-    // [5] callprepare next 
     // [5] callprepare next  -- _stackpushbyte_2 
     pha
     pha
-    // [5] callprepare next 
     // [6] callexecute next  -- jsr 
     jsr next
-    // [7] (signed word~) main::$0 ← callfinalize next 
     // [7] (signed word~) main::$0 ← callfinalize next  -- vwsz1=_stackpullsword_ 
     pla
     sta.z __0
@@ -375,14 +366,11 @@ main: {
     sta SCREEN
     lda.z __0+1
     sta SCREEN+1
-    // [9] callprepare next 
     // [9] callprepare next  -- _stackpushbyte_2 
     pha
     pha
-    // [9] callprepare next 
     // [10] callexecute next  -- jsr 
     jsr next
-    // [11] (signed word~) main::$1 ← callfinalize next 
     // [11] (signed word~) main::$1 ← callfinalize next  -- vwsz1=_stackpullsword_ 
     pla
     sta.z __1
@@ -490,14 +478,11 @@ main: {
     .label __0 = 2
     .label __1 = 4
     // next()
-    // [5] callprepare next 
     // [5] callprepare next  -- _stackpushbyte_2 
     pha
     pha
-    // [5] callprepare next 
     // [6] callexecute next  -- jsr 
     jsr next
-    // [7] (signed word~) main::$0 ← callfinalize next 
     // [7] (signed word~) main::$0 ← callfinalize next  -- vwsz1=_stackpullsword_ 
     pla
     sta.z __0
@@ -510,14 +495,11 @@ main: {
     lda.z __0+1
     sta SCREEN+1
     // next()
-    // [9] callprepare next 
     // [9] callprepare next  -- _stackpushbyte_2 
     pha
     pha
-    // [9] callprepare next 
     // [10] callexecute next  -- jsr 
     jsr next
-    // [11] (signed word~) main::$1 ← callfinalize next 
     // [11] (signed word~) main::$1 ← callfinalize next  -- vwsz1=_stackpullsword_ 
     pla
     sta.z __1