Implement IsRelative for cc65/merlin32

Added support for "relative" address regions to the Merlin 32 and cc65
code generators.  These generate "flat" address directives, and so
were a little more complicated.

Suppressed generation of relative operands for non-addressable regions.

Also, tweaked the 20250-nested-regions test to include a negative
relative region offset.

CommonUtil/AddressMap.cs

@@ -183,7 +183,7 @@ namespace CommonUtil {
             public int ActualLength { get; private set; }
 
             /// <summary>
-            /// Address associated with pre-label.
+            /// Address associated with pre-label and relative addressing.
             /// </summary>
             public int PreLabelAddress { get; private set; }
 
@@ -207,6 +207,19 @@ namespace CommonUtil {
                 }
             }
 
+            /// <summary>
+            /// Is this region validly marked "is relative"?
+            /// </summary>
+            /// <remarks>
+            /// The relative address is determined by subtracting the Address from the
+            /// PreLabelAddress, so neither may be NON_ADDR.
+            /// </remarks>
+            public bool HasValidIsRelative {
+                get {
+                    return IsRelative && PreLabelAddress != NON_ADDR && Address != NON_ADDR;
+                }
+            }
+
 
             /// <summary>
             /// Full constructor.

SourceGen/AsmGen/AsmAcme.cs

@@ -600,7 +600,7 @@ namespace SourceGen.AsmGen {
                 }
                 AddressMap.AddressRegion region = change.Region;
                 string addrStr;
-                if (region.IsRelative && region.PreLabelAddress != Address.NON_ADDR) {
+                if (region.HasValidIsRelative) {
                     int diff = nextAddress - region.PreLabelAddress;
                     string pfxStr;
                     if (diff >= 0) {

SourceGen/AsmGen/AsmCc65.cs

@@ -96,6 +96,18 @@ namespace SourceGen.AsmGen {
         /// </summary>
         private int mNextAddress = -1;
 
+        /// <summary>
+        /// True if we've seen an "is relative" flag in a block of address region start directives.
+        /// </summary>
+        /// <remarks>
+        /// The trick with IsRelative is that, if there are multiple arstarts at the same
+        /// offset, we need to output some or all of them, starting from the one just before
+        /// the first IsRelative start.  We probably want to disable the use of Flush and
+        /// just generate them as they appear, using the next Flush as the signal to return
+        /// to standard behavior.
+        /// </remarks>
+        bool mIsInRelative = false;
+
         /// <summary>
         /// Holds detected version of configured assembler.
         /// </summary>
@@ -540,34 +552,73 @@ namespace SourceGen.AsmGen {
 
         // IGenerator
         public void OutputArDirective(CommonUtil.AddressMap.AddressChange change) {
-            if (change.IsStart && change.Region.HasValidPreLabel) {
-                // Need to output the previous ORG, if any, then a label on a line by itself.
-                if (mNextAddress >= 0) {
-                    OutputLine(string.Empty,
-                        SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
-                        SourceFormatter.FormatHexValue(mNextAddress, 4),
-                        string.Empty);
-                }
-                string labelStr = mLocalizer.ConvLabel(change.Region.PreLabel);
-                OutputLine(labelStr, string.Empty, string.Empty, string.Empty);
-            }
-
             int nextAddress = change.Address;
             if (nextAddress == Address.NON_ADDR) {
                 // Start non-addressable regions at zero to ensure they don't overflow bank.
                 nextAddress = 0;
             }
+
+            if (change.IsStart) {
+                AddressMap.AddressRegion region = change.Region;
+                if (region.HasValidPreLabel || region.HasValidIsRelative) {
+                    // Need to output the previous ORG, if one is pending.
+                    if (mNextAddress >= 0) {
+                        OutputLine(string.Empty,
+                            SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+                            SourceFormatter.FormatHexValue(mNextAddress, 4),
+                            string.Empty);
+                    }
+                }
+                if (region.HasValidPreLabel) {
+                    string labelStr = mLocalizer.ConvLabel(change.Region.PreLabel);
+                    OutputLine(labelStr, string.Empty, string.Empty, string.Empty);
+                }
+                if (region.HasValidIsRelative) {
+                    // Found a valid IsRelative.  Switch to "relative mode" if not there already.
+                    mIsInRelative = true;
+                }
+                if (mIsInRelative) {
+                    // Once we see a region with IsRelative set, we output regions as we
+                    // find them until the next Flush.
+                    string addrStr;
+                    if (region.HasValidIsRelative) {
+                        int diff = nextAddress - region.PreLabelAddress;
+                        string pfxStr;
+                        if (diff >= 0) {
+                            pfxStr = "*+";
+                        } else {
+                            pfxStr = "*-";
+                            diff = -diff;
+                        }
+                        addrStr = pfxStr + SourceFormatter.FormatHexValue(diff, 4);
+                    } else {
+                        addrStr = SourceFormatter.FormatHexValue(nextAddress, 4);
+                    }
+                    OutputLine(string.Empty,
+                        SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+                        addrStr, string.Empty);
+
+                    mNextAddress = -1;
+                    return;
+                }
+            }
+
             mNextAddress = nextAddress;
         }
 
         // IGenerator
         public void FlushArDirectives() {
-            // TODO(someday): handle IsRelative
+            // Output pending directives.  There will always be something to do here unless
-            OutputLine(string.Empty,
+            // we were in "relative" mode.
-                SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+            Debug.Assert(mNextAddress >= 0 || mIsInRelative);
-                SourceFormatter.FormatHexValue(mNextAddress, 4),
+            if (mNextAddress >= 0) {
-                string.Empty);
+                OutputLine(string.Empty,
+                    SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+                    SourceFormatter.FormatHexValue(mNextAddress, 4),
+                    string.Empty);
+            }
             mNextAddress = -1;
+            mIsInRelative = false;
         }
 
         // IGenerator

SourceGen/AsmGen/AsmMerlin32.cs

@@ -91,6 +91,18 @@ namespace SourceGen.AsmGen {
         /// </summary>
         private int mNextAddress = -1;
 
+        /// <summary>
+        /// True if we've seen an "is relative" flag in a block of address region start directives.
+        /// </summary>
+        /// <remarks>
+        /// The trick with IsRelative is that, if there are multiple arstarts at the same
+        /// offset, we need to output some or all of them, starting from the one just before
+        /// the first IsRelative start.  We probably want to disable the use of Flush and
+        /// just generate them as they appear, using the next Flush as the signal to return
+        /// to standard behavior.
+        /// </remarks>
+        bool mIsInRelative = false;
+
         /// <summary>
         /// Holds detected version of configured assembler.
         /// </summary>
@@ -491,35 +503,75 @@ namespace SourceGen.AsmGen {
 
         // IGenerator
         public void OutputArDirective(CommonUtil.AddressMap.AddressChange change) {
-            if (change.IsStart && change.Region.HasValidPreLabel) {
-                // Need to output the previous ORG, if any, then a label on a line by itself.
-                if (mNextAddress >= 0) {
-                    OutputLine(string.Empty,
-                        SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
-                        SourceFormatter.FormatHexValue(mNextAddress, 4),
-                        string.Empty);
-                }
-                string labelStr = mLocalizer.ConvLabel(change.Region.PreLabel);
-                OutputLine(labelStr, string.Empty, string.Empty, string.Empty);
-            }
-
             int nextAddress = change.Address;
             if (nextAddress == Address.NON_ADDR) {
                 // Start non-addressable regions at zero to ensure they don't overflow bank.
                 nextAddress = 0;
             }
+
+            if (change.IsStart) {
+                AddressMap.AddressRegion region = change.Region;
+                if (region.HasValidPreLabel || region.HasValidIsRelative) {
+                    // Need to output the previous ORG, if one is pending.
+                    if (mNextAddress >= 0) {
+                        OutputLine(string.Empty,
+                            SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+                            SourceFormatter.FormatHexValue(mNextAddress, 4),
+                            string.Empty);
+                    }
+                }
+                if (region.HasValidPreLabel) {
+                    string labelStr = mLocalizer.ConvLabel(change.Region.PreLabel);
+                    OutputLine(labelStr, string.Empty, string.Empty, string.Empty);
+                }
+                if (region.HasValidIsRelative) {
+                    // Found a valid IsRelative.  Switch to "relative mode" if not there already.
+                    mIsInRelative = true;
+                }
+                if (mIsInRelative) {
+                    // Once we see a region with IsRelative set, we output regions as we
+                    // find them until the next Flush.
+                    string addrStr;
+                    if (region.HasValidIsRelative) {
+                        Debug.Assert(nextAddress != Address.NON_ADDR &&
+                            region.PreLabelAddress != Address.NON_ADDR);
+                        int diff = nextAddress - region.PreLabelAddress;
+                        string pfxStr;
+                        if (diff >= 0) {
+                            pfxStr = "*+";
+                        } else {
+                            pfxStr = "*-";
+                            diff = -diff;
+                        }
+                        addrStr = pfxStr + SourceFormatter.FormatHexValue(diff, 4);
+                    } else {
+                        addrStr = SourceFormatter.FormatHexValue(nextAddress, 4);
+                    }
+                    OutputLine(string.Empty,
+                        SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+                        addrStr, string.Empty);
+
+                    mNextAddress = -1;
+                    return;
+                }
+            }
+
             mNextAddress = nextAddress;
         }
 
         // IGenerator
         public void FlushArDirectives() {
-            // TODO(someday): handle IsRelative
+            // Output pending directives.  There will always be something to do here unless
-            Debug.Assert(mNextAddress >= 0);
+            // we were in "relative" mode.
-            OutputLine(string.Empty,
+            Debug.Assert(mNextAddress >= 0 || mIsInRelative);
-                SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+            if (mNextAddress >= 0) {
-                SourceFormatter.FormatHexValue(mNextAddress, 4),
+                OutputLine(string.Empty,
-                string.Empty);
+                    SourceFormatter.FormatPseudoOp(sDataOpNames.ArStartDirective),
+                    SourceFormatter.FormatHexValue(mNextAddress, 4),
+                    string.Empty);
+            }
             mNextAddress = -1;
+            mIsInRelative = false;
         }
 
         // IGenerator

SourceGen/AsmGen/AsmTass64.cs

@@ -709,7 +709,7 @@ namespace SourceGen.AsmGen {
 
                 AddressMap.AddressRegion region = change.Region;
                 string addrStr;
-                if (region.IsRelative && region.PreLabelAddress != Address.NON_ADDR) {
+                if (region.HasValidIsRelative) {
                     int diff = nextAddress - region.PreLabelAddress;
                     string pfxStr;
                     if (diff >= 0) {

SourceGen/AsmGen/GenCommon.cs

@@ -90,6 +90,7 @@ namespace SourceGen.AsmGen {
                     }
                 }
 
+                // Reached end of start directives.  Write the last one.
                 if (arDirectPending) {
                     gen.FlushArDirectives();
                     arDirectPending = false;

SourceGen/LineListGen.cs

@@ -1095,8 +1095,7 @@ namespace SourceGen {
                         string addrStr;
                         if (region.Address == Address.NON_ADDR) {
                             addrStr = Address.NON_ADDR_STR;
-                        } else if (change.Region.IsRelative &&
+                        } else if (change.Region.HasValidIsRelative) {
-                                change.Region.PreLabelAddress != Address.NON_ADDR) {
                             int diff = region.Address - change.Region.PreLabelAddress;
                             string pfxStr;
                             if (diff >= 0) {

SourceGen/SGTestData/20250-nested-regions.dis65

@@ -2,7 +2,7 @@
 {
 "_ContentVersion":5,
 "FileDataLength":156,
-"FileDataCrc32":1681364707,
+"FileDataCrc32":367497130,
 "ProjectProps":{
 "CpuName":"6502",
 "IncludeUndocumentedInstr":false,
@@ -74,17 +74,17 @@
 
 {
 "Offset":132,
-"Addr":53248,
+"Addr":57344,
 "Length":24,
 "PreLabel":"",
 "IsRelative":true},
 
 {
 "Offset":139,
-"Addr":57344,
+"Addr":53248,
 "Length":17,
 "PreLabel":"",
-"IsRelative":false},
+"IsRelative":true},
 
 {
 "Offset":145,

SourceGen/SGTestData/Expected/20250-nested-regions_64tass.S

@@ -7,7 +7,7 @@
         .logical *+$1000
 L3000   bit     L3000
 _L3003  lda     _L3003
-        and     _LD003
+        and     _LE003
         jmp     _L200C
 
         .here
@@ -22,7 +22,7 @@ _L1012  bit     _L1012
         .null   "Null-term PETSCII string"
         .byte   $80
         .word   _L3003
-        .word   _LD003
+        .word   _LE003
         .byte   $80
         .here
 
@@ -72,22 +72,22 @@ _L5017  rts
 _L4040  bit     _L4040
         bit     _L5017
         nop
-        jmp     _LD000
-
-        .here
-        .logical *+$bf7e
-_LD000  bit     _L200C
-_LD003  nop
         jmp     _LE000
 
-        .logical $e000
+        .here
-_LE000  bit     _LE000
+        .logical *+$cf7e
+_LE000  bit     _L200C
+_LE003  nop
+        jmp     _LD000
+
+        .logical *-$1007
+_LD000  bit     _LD000
         jmp     _LF000
 
         .logical $f000
 _LF000  bit     _LF000
         lda     _L3003
-        and     _LD003
+        and     _LE003
         nop
         rts
 

SourceGen/SGTestData/Expected/20250-nested-regions_acme.S

@@ -7,7 +7,7 @@
         !pseudopc *+$1000 {
 L3000   bit     L3000
 @L3003  lda     @L3003
-        and     @LD003
+        and     @LE003
         jmp     @L200C
 
         }
@@ -22,7 +22,7 @@ L3000   bit     L3000
         !pet    "Null-term PETSCII string",$00
         !byte   $80
         !word   @L3003
-        !word   @LD003
+        !word   @LE003
         !byte   $80
         }
 
@@ -72,22 +72,22 @@ L3000   bit     L3000
 @L4040  bit     @L4040
         bit     @L5017
         nop
-        jmp     @LD000
-
-        }
-        !pseudopc *+$bf7e {
-@LD000  bit     @L200C
-@LD003  nop
         jmp     @LE000
 
-        !pseudopc $e000 {
+        }
-@LE000  bit     @LE000
+        !pseudopc *+$cf7e {
+@LE000  bit     @L200C
+@LE003  nop
+        jmp     @LD000
+
+        !pseudopc *-$1007 {
+@LD000  bit     @LD000
         jmp     @LF000
 
         !pseudopc $f000 {
 @LF000  bit     @LF000
         lda     @L3003
-        and     @LD003
+        and     @LE003
         nop
         rts
 

SourceGen/SGTestData/Expected/20250-nested-regions_cc65.S

@@ -2,10 +2,12 @@
          .org    $0000
          .word   $3000      ;load address
 
-         .org    $3000
+         .org    $1000
+         .org    *+$1000
+         .org    *+$1000
 L3000:   bit     L3000
 @L3003:  lda     @L3003
-         and     @LD003
+         and     @LE003
          jmp     @L200C
 
          .org    $200c
@@ -21,7 +23,7 @@ L3000:   bit     L3000
          .byte   $c9,$20,$53,$54,$52,$49,$4e,$47,$00
          .byte   $80
          .word   @L3003
-         .word   @LD003
+         .word   @LE003
          .byte   $80
 
          .org    $4000
@@ -70,21 +72,22 @@ L3000:   bit     L3000
 @L4040:  bit     @L4040
          bit     @L5017
          nop
-         jmp     @LD000
-
-         .org    $d000
-@LD000:  bit     @L200C
-@LD003:  nop
          jmp     @LE000
 
-         .org    $e000
+         .org    $1082
-@LE000:  bit     @LE000
+         .org    *+$cf7e
+@LE000:  bit     @L200C
+@LE003:  nop
+         jmp     @LD000
+
+         .org    *-$1007
+@LD000:  bit     @LD000
          jmp     @LF000
 
          .org    $f000
 @LF000:  bit     @LF000
          lda     @L3003
-         and     @LD003
+         and     @LE003
          nop
          rts
 

SourceGen/SGTestData/Expected/20250-nested-regions_merlin32.S

@@ -1,10 +1,12 @@
          org   $0000
          dw    $3000      ;load address
 
-         org   $3000
+         org   $1000
+         org   *+$1000
+         org   *+$1000
 L3000    bit   L3000
 :L3003   lda   :L3003
-         and   :LD003
+         and   :LE003
          jmp   :L200C
 
          org   $200c
@@ -19,7 +21,7 @@ L3000    bit   L3000
          hex   ce554c4c2d5445524d20d0c5d4d3c3c9c920535452494e4700
          dfb   $80
          dw    :L3003
-         dw    :LD003
+         dw    :LE003
          dfb   $80
 
          org   $4000
@@ -68,21 +70,22 @@ L3000    bit   L3000
 :L4040   bit   :L4040
          bit   :L5017
          nop
-         jmp   :LD000
-
-         org   $d000
-:LD000   bit   :L200C
-:LD003   nop
          jmp   :LE000
 
-         org   $e000
+         org   $1082
-:LE000   bit   :LE000
+         org   *+$cf7e
+:LE000   bit   :L200C
+:LE003   nop
+         jmp   :LD000
+
+         org   *-$1007
+:LD000   bit   :LD000
          jmp   :LF000
 
          org   $f000
 :LF000   bit   :LF000
          lda   :L3003
-         and   :LD003
+         and   :LE003
          nop
          rts
 

SourceGen/SGTestData/Expected/20252-nested-regions_64tass.S

@@ -18,7 +18,7 @@ _L11018 lda     _L11018
         jmp     _L11026
 
 _L1101F .byte   $80
-        .logical *-$011020
+        .logical $0000
         .byte   $ea
         .byte   $60
         .dword  _L31004

SourceGen/SGTestData/Expected/20252-nested-regions_cc65.S

@@ -1,5 +1,7 @@
          .setcpu "65816"
-         .org    $031000
+         .org    $011000
+         .org    *+$010000
+         .org    *+$010000
          .a8
          .i8
 L31000:  lda     L31000

SourceGen/SGTestData/Expected/20252-nested-regions_merlin32.S

@@ -1,4 +1,6 @@
-         org   $031000
+         org   $011000
+         org   *+$010000
+         org   *+$010000
 L31000   ldal  L31000
 :L31004  ldal  :L31004
          andl  :L1101F

SourceGen/SGTestData/Source/20250-nested-regions.S

@@ -107,17 +107,17 @@ a4040   bit     a4040
         .here               ;$4000
 
 
+; EDIT: create region starting at $e000, ending at REGION2_END; relative
+        .logical $e000
+tailend
+partek  bit     part2k
+late    nop
+        jmp     partdk
+
 ; EDIT: create region starting at $d000, ending at REGION2_END; relative
         .logical $d000
-tailend
-partdk  bit     part2k
-late    nop
-        jmp     partek
 
-; EDIT: create
+partdk  bit     partdk
-        .logical $e000
-
-partek  bit     partek
         jmp     partfk
 
 ; EDIT: create, make it floating