CosmOS pre-alpha and launchable application versions of old programs.

2026-08-17 15:31:49 -04:00
parent eff6902bcf
commit 91c9d49d1b
66 changed files with 5612 additions and 160 deletions
@@ -0,0 +1,230 @@
+; The 16-bit segmented sieve rewritten for SplitBit's four-Data-Pointer ISA.
+;
+; This deliberately implements the same algorithm and emits the same text as
+; 16bitSegmentedSieve.asm, making the two versions useful as a direct comparison.
+; DP0 walks PrimeStates, DP1 holds Page, DP2 walks Segment, and volatile DP3
+; marks multiples.  CALL preserves the first three pointers automatically.
+
+#Include services.asm
+
+#Program
+
+    #Base 0x2000
+
+start:
+  RSTA
+  SETD.1 Page
+  STA.1
+
+nextPage:
+  SETD.2 Segment
+  RSTA
+  RSTB
+clearSegment:
+  STB.2
+  INCD.2
+  INCA
+  BRA segmentCleared
+  BRI clearSegment
+
+segmentCleared:
+  ; Zero and one are not prime.
+  LDA.1
+  BRA excludeZeroAndOne
+  BRI markSegment
+excludeZeroAndOne:
+  SETD.2 Segment
+  INIA 0x01
+  STA.2
+  INCD.2
+  STA.2
+
+markSegment:
+  SETD.0 PrimeStates
+  INIA 0d54
+primeLoop:
+  CALL processPrime
+  DPUP.0 0d03
+  DECA
+  BRA scanSegment
+  BRI primeLoop
+
+scanSegment:
+  SETD.2 Segment
+  RSTA
+scanLoop:
+  LDB.2
+  BRB emitPrime
+scanNext:
+  INCD.2
+  INCA
+  BRA advancePage
+  BRI scanLoop
+
+emitPrime:
+  CALL printCandidateHex
+  BRI scanNext
+
+advancePage:
+  LDA.1
+  INCA
+  STA.1
+  BRA finished
+  BRI nextPage
+
+finished:
+  CALL lineFeed
+  SWI osExit  ; Return to CosmOS.
+
+; DP0 points at a PrimeStates entry. CALL restores it on return.
+processPrime:
+  INCD.0
+  LDA.0
+  LDB.1
+  XOR
+  BRQ primeIsActive
+  RET
+
+primeIsActive:
+  ; B is the prime and A its current offset.
+  DECD.0
+  LDB.0
+  DPUP.0 0d02
+  LDA.0
+
+  ; DP3 = Segment + offset. Only this one initial pointer copy needs the Stack.
+  SETD.3 Segment
+  PSHB
+  PSHD.3
+  POPB
+  CCF
+  ADD
+  PSHQ
+  POPD.3
+  POPB
+
+markPrimeLoop:
+  INIA 0x01
+  STA.3
+
+  ; Add the prime to DP3's low byte. A carry crosses into the next window.
+  PSHD.3
+  POPA
+  CCF
+  ADD
+  PSHQ
+  POPD.3
+  BRC primeFinished
+  BRI markPrimeLoop
+
+primeFinished:
+  ; DP0 is on the offset byte; advance the saved high byte and save Q as
+  ; the wrapped offset for the following page.
+  DECD.0
+  LDA.0
+  INCA
+  STA.0
+  INCD.0
+  STQ.0
+  RET
+
+printCandidateHex:
+  PSHA
+  LDA.1
+  CALL printByteHex
+  POPA
+  CALL printByteHex
+  CALL blankSpace
+  RET
+
+#Data
+
+  #Base 0x1000
+
+; Segment has to begin on a page boundary, and now says so itself rather than relying on
+; whatever happens to have been assembled before it. The marking loop adds the prime to
+; the low byte of DP3 and treats the carry out as the end of the page, so it only finds
+; the right boundary if the window starts on one.
+;
+; The whole window is written out here so that Page and PrimeStates begin after it.
+
+  #Align 0x100
+Segment:
+  0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+  0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
+
+Page:
+  0x00
+
+PrimeStates:
+  0x02 0x00 0x04
+  0x03 0x00 0x09
+  0x05 0x00 0x19
+  0x07 0x00 0x31
+  0x0B 0x00 0x79
+  0x0D 0x00 0xA9
+  0x11 0x01 0x21
+  0x13 0x01 0x69
+  0x17 0x02 0x11
+  0x1D 0x03 0x49
+  0x1F 0x03 0xC1
+  0x25 0x05 0x59
+  0x29 0x06 0x91
+  0x2B 0x07 0x39
+  0x2F 0x08 0xA1
+  0x35 0x0A 0xF9
+  0x3B 0x0D 0x99
+  0x3D 0x0E 0x89
+  0x43 0x11 0x89
+  0x47 0x13 0xB1
+  0x49 0x14 0xD1
+  0x4F 0x18 0x61
+  0x53 0x1A 0xE9
+  0x59 0x1E 0xF1
+  0x61 0x24 0xC1
+  0x65 0x27 0xD9
+  0x67 0x29 0x71
+  0x6B 0x2C 0xB9
+  0x6D 0x2E 0x69
+  0x71 0x31 0xE1
+  0x7F 0x3F 0x01
+  0x83 0x43 0x09
+  0x89 0x49 0x51
+  0x8B 0x4B 0x79
+  0x95 0x56 0xB9
+  0x97 0x59 0x11
+  0x9D 0x60 0x49
+  0xA3 0x67 0xC9
+  0xA7 0x6C 0xF1
+  0xAD 0x74 0xE9
+  0xB3 0x7D 0x29
+  0xB5 0x7F 0xF9
+  0xBF 0x8E 0x81
+  0xC1 0x91 0x81
+  0xC5 0x97 0x99
+  0xC7 0x9A 0xB1
+  0xD3 0xAD 0xE9
+  0xDF 0xC2 0x41
+  0xE3 0xC9 0x49
+  0xE5 0xCC 0xD9
+  0xE9 0xD4 0x11
+  0xEF 0xDF 0x21
+  0xF1 0xE2 0xE1
+  0xFB 0xF6 0x19
+
+#Include print.asm