Allow LOAD FRAGMENT (#1552)

This was implemented in #736 but removed after discussion in #869.

Fixes #1537

Author: Rangi42

man/rgbasm.5

@@ -968,11 +968,11 @@ block before performing its own function.
 .Ic LOAD
 blocks can use the
 .Ic UNION
-modifier as described in
-.Sx Unionized sections
-below, but not the
+or
 .Ic FRAGMENT
-modifier.
+modifiers as described in
+.Sx Unionized sections
+below.
 .Ss Unionized sections
 When you're tight on RAM, you may want to define overlapping static memory allocations, as explained in the
 .Sx Allocating overlapping spaces in RAM

src/asm/section.cpp

@@ -462,11 +462,6 @@ void sect_SetLoadSection(
 		return;
 	}
 
-	if (mod == SECTION_FRAGMENT) {
-		error("`LOAD FRAGMENT` is not allowed\n");
-		return;
-	}
-
 	if (currentLoadSection)
 		sect_EndLoadSection("LOAD");
 

test/asm/load-fragment.asm

@@ -1,2 +1,29 @@
 SECTION "A", ROM0
+AData::
 LOAD FRAGMENT "RAM", WRAM0
+AMem::
+	db 0, 1, 2
+AMemEnd::
+ENDL
+ADataEnd::
+	dw AMem
+
+SECTION "B", ROM0
+BData::
+LOAD FRAGMENT "RAM", WRAM0
+BMem::
+	db 3, 4, 5, 6, 7
+BMemEnd::
+ENDL
+BDataEnd::
+	dw BMem
+
+SECTION "C", ROM0
+CData::
+LOAD FRAGMENT "RAM", WRAM0
+CMem::
+	db 8, 9
+CMemEnd::
+ENDL
+CDataEnd::
+	dw CMem

test/asm/load-fragment.err

@@ -0,0 +1,12 @@
+SECTION "main", ROM0
+LOAD FRAGMENT "test", SRAM
+ENDL
+
+; The RPN patch for 'jr Label' in section "alt" refers to section "test",
+; but the object file puts section "test" after section "alt".
+; This case needs to be handled when identifying patches' PC sections.
+SECTION "alt", ROM0
+LOAD FRAGMENT "test", SRAM
+	jr Label
+Label:
+ENDL

test/asm/load-fragment.out.bin

@@ -0,0 +1,9 @@
+SECTION "Test", ROM0[0]
+AA: db 1
+LOAD FRAGMENT "RAM section", WRAM0[$c000]
+BB: db 2
+ENDL
+CC: db 3
+LOAD FRAGMENT "RAM section", WRAM0
+DD: db 4
+ENDL

test/link/load-fragment-jr.asm

@@ -0,0 +1 @@
+


test/link/load-fragment-jr.out

@@ -0,0 +1,5 @@
+; File generated by rgblink
+00:0000 AA
+00:0002 CC
+00:c000 BB
+00:c001 DD

test/link/load-fragment-jr.out.bin

@@ -0,0 +1,4 @@
+SECTION "main", ROM0
+LOAD FRAGMENT "test", SRAM
+	db 0
+ENDL

test/link/load-fragment/base/a.asm

@@ -0,0 +1,6 @@
+SECTION "SECTION2", ROM0
+LOAD FRAGMENT "test", SRAM
+	jr Label
+Label:
+	dw Label
+ENDL

test/link/load-fragment/base/ref.out.bin

@@ -0,0 +1,8 @@
+SECTION FRAGMENT "rom", ROM0
+Part1::
+LOAD FRAGMENT "ram", WRAM0
+wPart1::
+	jr wPart1
+	jr wPart3
+ENDL
+Part1End::

test/link/load-fragment/base/ref.out.sym

@@ -0,0 +1,4 @@
+SECTION FRAGMENT "rom", ROM0
+Part2::
+db "Hello world!"
+Part2End::

test/link/load-fragment/multiple-objects/a.asm

@@ -0,0 +1,8 @@
+SECTION FRAGMENT "rom", ROM0
+Part3::
+LOAD FRAGMENT "ram", WRAM0
+wPart3::
+	jr wPart1
+	jr wPart3
+ENDL
+Part3End::

test/link/load-fragment/multiple-objects/b.asm

@@ -0,0 +1,24 @@
+SUMMARY:
+	ROM0: 20 bytes used / 16364 free
+	WRAM0: 8 bytes used / 4088 free
+
+ROM0 bank #0:
+	SECTION: $0000-$0013 ($0014 bytes) ["rom"]
+	         $0000 = Part1
+	         $0004 = Part1End
+	         ; Next fragment
+	         $0010 = Part3
+	         $0014 = Part3End
+	         ; Next fragment
+	         $0004 = Part2
+	         $0010 = Part2End
+	EMPTY: $0014-$3fff ($3fec bytes)
+	TOTAL EMPTY: $3fec bytes
+
+WRAM0 bank #0:
+	SECTION: $c000-$c007 ($0008 bytes) ["ram"]
+	         $c000 = wPart1
+	         ; Next fragment
+	         $c004 = wPart3
+	EMPTY: $c008-$cfff ($0ff8 bytes)
+	TOTAL EMPTY: $0ff8 bytes

test/link/load-fragment/multiple-objects/ref.out.bin

@@ -0,0 +1,9 @@
+; File generated by rgblink
+00:0000 Part1
+00:0004 Part1End
+00:0004 Part2
+00:0010 Part3
+00:0010 Part2End
+00:0014 Part3End
+00:c000 wPart1
+00:c004 wPart3

test/link/load-fragment/section-fragment/a.asm

@@ -0,0 +1,4 @@
+SECTION FRAGMENT "output", ROM0
+LOAD FRAGMENT "loaded", SRAM
+    ds 128
+ENDL

test/link/load-fragment/section-fragment/b.asm

@@ -0,0 +1,6 @@
+SECTION FRAGMENT "output", ROM0
+LOAD FRAGMENT "loaded", SRAM
+label:
+	jr nz, label2
+label2:
+ENDL

test/link/load-fragment/section-fragment/c.asm

@@ -172,6 +172,36 @@ rgblinkQuiet -o "$gbtemp2" "$outtemp"
 tryCmp "$gbtemp" "$gbtemp2"
 evaluateTest
 
+test="load-fragment/base"
+startTest
+"$RGBASM" -o "$otemp" "$test"/a.asm
+continueTest
+rgblinkQuiet -o "$gbtemp" -n "$outtemp" "$otemp"
+tryCmpRom "$test"/ref.out.bin
+tryDiff "$test"/ref.out.sym "$outtemp"
+evaluateTest
+
+test="load-fragment/multiple-objects"
+startTest
+"$RGBASM" -o "$otemp" "$test"/a.asm
+"$RGBASM" -o "$gbtemp2" "$test"/b.asm
+continueTest
+rgblinkQuiet -o "$gbtemp" "$otemp" "$gbtemp2"
+tryCmpRom "$test"/ref.out.bin
+evaluateTest
+
+test="load-fragment/section-fragment"
+startTest
+"$RGBASM" -o "$otemp" "$test"/a.asm
+"$RGBASM" -o "$outtemp" "$test"/b.asm
+"$RGBASM" -o "$outtemp2" "$test"/c.asm
+continueTest
+rgblinkQuiet -o "$gbtemp" -m "$outtemp3" -n "$gbtemp2" "$otemp" "$outtemp" "$outtemp2"
+tryCmpRom "$test"/ref.out.bin
+tryDiff "$test"/ref.out.map "$outtemp3"
+tryDiff "$test"/ref.out.sym "$gbtemp2"
+evaluateTest
+
 test="map-file"
 startTest
 "$RGBASM" -o "$otemp" "$test"/a.asm
@@ -257,6 +287,15 @@ rgblinkQuiet -o "$gbtemp" "$otemp" "$gbtemp2"
 tryCmpRom "$test"/ref.out.bin
 evaluateTest
 
+test="section-fragment/jr-offset-load"
+startTest
+"$RGBASM" -o "$otemp" "$test"/a.asm
+"$RGBASM" -o "$gbtemp2" "$test"/b.asm
+continueTest
+rgblinkQuiet -o "$gbtemp" "$otemp" "$gbtemp2"
+tryCmpRom "$test"/ref.out.bin
+evaluateTest
+
 test="section-normal/same-name"
 startTest
 "$RGBASM" -o "$otemp" "$test"/a.asm