about summary refs log tree commit diff stats
diff options
context:
space:
mode:
-rw-r--r--apps/survey.subx25
1 files changed, 18 insertions, 7 deletions
diff --git a/apps/survey.subx b/apps/survey.subx
index a74f7273..4a84baa4 100644
--- a/apps/survey.subx
+++ b/apps/survey.subx
@@ -620,6 +620,10 @@ compute-offsets:segment-tmp:  # slice
 
 == code
 
+# write segments->file-offset,
+#       segments->size,
+#       labels->segment-name, and
+#       labels->segment-offset
 compute-offsets:  # in: (addr stream byte), segments: (addr stream {string, segment-info}), labels: (addr stream {string, label-info})
     # skeleton:
     #   for lines in 'in'
@@ -631,7 +635,9 @@ compute-offsets:  # in: (addr stream byte), segments: (addr stream {string, segm
     #         default
     #
     # pseudocode:
-    #   curr-segment-name: (addr string) = 0
+    #   var curr-segment-name: (addr string) = 0
+    #   var file-offset = 0
+    #   var segment-offset = 0
     #   var line: (stream byte 512)
     #   while true                                  # line loop
     #     clear-stream(line)
@@ -646,7 +652,7 @@ compute-offsets:  # in: (addr stream byte), segments: (addr stream {string, segm
     #       else if slice-equal?(word-slice, "==")
     #         if curr-segment-name != 0
     #           seg = get-or-insert(segments, curr-segment-name)
-    #           seg->size = *file-offset - seg->file-offset
+    #           seg->size = file-offset - seg->file-offset
     #           trace("segment '", curr-segment-name, "' has size ", seg->size)
     #         segment-tmp = next-word(line)
     #         curr-segment-name = slice-to-string(segment-tmp)
@@ -657,7 +663,7 @@ compute-offsets:  # in: (addr stream byte), segments: (addr stream {string, segm
     #           abort
     #         seg = get-or-insert(segments, curr-segment-name)
     #         seg->starting-address = parse-hex-int-from-slice(segment-tmp)
-    #         seg->file-offset = *file-offset
+    #         seg->file-offset = file-offset
     #         trace("segment '", curr-segment-name, "' is at file offset ", seg->file-offset)
     #         segment-offset = 0
     #         break  (next line)
@@ -671,8 +677,10 @@ compute-offsets:  # in: (addr stream byte), segments: (addr stream {string, segm
     #         # labels occupy no space, so no need to increment offsets
     #       else
     #         width = compute-width-of-slice(word-slice)
-    #         *segment-offset += width
-    #         *file-offset += width
+    #         segment-offset += width
+    #         file-offset += width
+    #   seg = get-or-insert-handle(segments, curr-segment-name)
+    #   seg->size = file-offset - seg->file-offset
     #
     # . prologue
     55/push-ebp
@@ -687,9 +695,9 @@ compute-offsets:  # in: (addr stream byte), segments: (addr stream {string, segm
     # curr-segment-name/esi = 0
     31/xor                          3/mod/direct    6/rm32/esi    .           .             .           6/r32/esi   .               .                 # clear esi
     # file-offset = 0
-    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:file-offset/disp32  0/imm32  # copy to *compute-offsets:word-slice
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:file-offset/disp32  0/imm32  # copy to *compute-offsets:file-offset
     # segment-offset = 0
-    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:segment-offset/disp32  0/imm32  # copy to *compute-offsets:word-slice
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:segment-offset/disp32  0/imm32  # copy to *compute-offsets:segment-offset
     # var line/ecx: (stream byte 512)
     81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0x200/imm32       # subtract from esp
     68/push  0x200/imm32/size
@@ -1377,6 +1385,9 @@ test-compute-offsets:
     5d/pop-to-ebp
     c3/return
 
+# write segments->file-offset,
+#       segments->address, and
+#       labels->address
 compute-addresses:  # segments: (addr stream {string, segment-info}), labels: (addr stream {string, label-info})
     # pseudocode:
     #   srow: (addr segment-info) = segments->data