Correction: The code fails in the simulator too. I forgot to link in libfp and libc in my simulator make file. :)
-Chris -----Original Message----- From: Takahashi, Chris [mailto:chris.takaha...@fluke.com] Sent: Monday, August 04, 2003 3:07 PM To: Mspgcc-Users (E-mail) Subject: [Mspgcc-users] more libfp problems. The patch msp430-libc/src/libm fixsfsi.c,1.4,1.5 mulsf.c,1.6,1.7 seems to work but there appear to be more problems with libfp. While testing this update I noticed that there were still problems when I linked in libfp. I narrowed the problem down to >=, <=, <, and > evaluation with floating point numbers. After examining __gesf2 and the asm generated to call __gesf2 I noticed that the code to return from __gesf2 seems faulty: a[1] = (small >= big); //0 8092: 0b 43 clr r11 ; 8094: 1e 41 04 00 mov 4(r1), r14 ; 8098: 1f 41 06 00 mov 6(r1), r15 ; 809c: 2c 41 mov @r1, r12 ; 809e: 1d 41 02 00 mov 2(r1), r13 ; 80a2: b0 12 b4 81 call #-32332 ;#0x81b4 80a6: 0f 93 cmp #0, r15 ;r3 As==00 80a8: 01 38 jl $+4 ;abs 0x80ac 80aa: 1b 43 mov #1, r11 ;r3 As==01 80ac: 81 4b 12 00 mov r11, 18(r1) ; where addr 0x81b4 is __gesf2. Because __gesf2 always returns a 0 or a 1 cmp will never set the negative flag and because cmp here does r15 - 0 the V flag will never be set either. Oddly enough the tests for >= and <= I wrote work with the simulator. I believe that the other operations may have similar problems. Attached are my simulator (tests.c) source and my regular test (test.c) source. -Chris
