2018-09-28 17:05:11 +00:00
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; Copyright 2018 faddenSoft. All Rights Reserved.
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; See the LICENSE.txt file for distribution terms (Apache 2.0).
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;
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; Assembler: Merlin 32
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2020-10-19 03:30:42 +00:00
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; 65816 version
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2018-09-28 17:05:11 +00:00
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org $1000
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jsr test2
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2020-10-19 03:30:42 +00:00
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jmp test6
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2018-09-28 17:05:11 +00:00
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; TEST #2: embedded with break path
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;
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; Example inspired by incorrect analysis...
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;
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; The code analyzer sees:
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; beq {+03} ;jumps to the $8f
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; lda #$00
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; brk $8f
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; and stops, then pursues the branch. If we try to walk from top
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; to bottom, skipping forward by the full length of an instruction,
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; we'll appear to find ourselves in the middle of an embedded
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; instruction.
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;
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; This is different from the typical embedded instruction,
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; where the inner is contained entirely within the outer.
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2020-10-19 03:30:42 +00:00
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;
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; (Not sure this is interesting anymore with default 1-byte BRK.)
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2018-09-28 17:05:11 +00:00
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test2 sep #$30 ;short regs
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mx %00 ;pretend they're long
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lda $00 ;load something to scramble flags
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2020-10-19 03:30:42 +00:00
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beq :store1
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2018-09-28 17:05:11 +00:00
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lda #$0000
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2020-10-19 03:30:42 +00:00
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:store1 stal $012345
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; Try it a different way. This creates two streams of execution.
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lda $00
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beq :store2
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lda #$8500
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:store2 stal $012345
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nop
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2018-09-28 17:05:11 +00:00
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rts
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; TEST #6: "embedded" off the end of the file
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2020-10-19 03:30:42 +00:00
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test6
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2018-09-28 17:05:11 +00:00
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dfb $af ;ldal
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