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Length: 948 (0x3b4)
Types: TextFile
Notes: UNIX file
Names: »dcmp.s«
└─⟦f27320a65⟧ Bits:30001972 Commodore 900 hard disk image with partial source code
└─⟦f4b8d8c84⟧ UNIX V7 Filesystem
└─ ⟦this⟧ »libc/crt/dcmp.s«
.globl dlcmp, drcmp / floating point package for segmented z-8001 / timothy s. murphy 10/84 / IEEE format / double: 63 62 52 51 0 / sign bin exp +1022 fraction (missing hi bit) / float: 31 30 23 22 0 / sign bin exp +126 fraction (missing hi bit) / .globl SS / signed compare of doubles a, b / return r1 = 1 if a > b / r1 = 0 if a = b / r1 = -1 if a < b / / drcmp( da, db) / dlcmp( da, &db) dlcmp: ldl rr2, SS|12(r15) jr un, 0f drcmp: lda rr2, SS|12(r15) 0: ldl rr4, (rr2) / b test r4 jr mi, 0f cpl rr4, SS|4(r15) jr gt, 9f / a < b jr lt, 7f / a > b / a is positive ldl rr4, rr2(4) cpl rr4, SS|8(r15) jr ugt, 9f jr ult, 7f jr 8f 0: / b negative ldl rr0, SS|4(r15) test r0 jr pl, 7f cpl rr4, rr0 jr ugt, 7f / abs(b) > abs(a) so a > b jr ult, 9f ldl rr4, rr2(4) cpl rr4, SS|8(r15) jr ugt, 7f jr ult, 9f 8: sub r1, r1 ret 7: ldk r1, $1 ret 9: ld r1, $-1 ret