From mboxrd@z Thu Jan 1 00:00:00 1970 Message-Id: From: diekema@bucks.si.com (diekema_jon) Subject: Floating Point problems with Linux on the EST SBC8260 To: linuxppc-embedded@lists.linuxppc.org Date: Wed, 24 May 2000 15:47:10 -0400 (EDT) Cc: all@cideas.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Floating Point problems with Linux on the EST SBC8260: Questions: - What is the state of floating point support with Linux on the MPC8260? - Does anybody have hard-float applications running on the MPC8260? - I am looking for a floating point validation test suite written in C. The test suite should start with the fundamentals and work out from there. Does anybody have any leads? This is what I have found so far: 1) TestFloat-2a Package Overview for TestFloat Release 2a John R. Hauser 1998 December 16 TestFloat is a program for testing that a floating-point implementation conforms to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. TestFloat is distributed in the form of C source code. The TestFloat package actually provides two related programs: -- The `testfloat' program tests a system's floating-point for conformance to the IEC/IEEE Standard. This program uses the SoftFloat software floating-point implementation as a basis for comparison. -- The `testsoftfloat' program tests SoftFloat itself for conformance to the IEC/IEEE Standard. These tests are performed by comparing against a separate, slower software floating-point that is included in the TestFloat package. 2) UCBTEST UCBTEST is a suite of programs for testing certain difficult cases of IEEE 754 floating-point arithmetic. Some of the difficult test cases are obtained from number-theoretic algorithms developed by Turing Award winner Prof. W. Kahan, Department of Electrical Engineering and Computer Science, University of California, Berkeley, as part of ongoing research into test methods for computer arithmetic. Either TestFloat or UCBTEST will require some porting effort to run on the PPC. I would like to work smarter rather than harder. I can't even get the rights answers from printf, *, or /. Environment: Platform: EST SBC8260 w/ MPC8260 Rev A.1 running at 166 Mhz Ethernet: 10 Mbs (SCC) Linux kernel: 2.3.99-pre9 root filesystem (NFS mounted): MontaVista Hard Hat Linux version 1.1 Toolset: Denx Software CDK recompiled with gcc configured for --with-cpu=603e and hard-float (i.e. no --nfp) Application: Note: The executable was statically linked to pull in the hard-float C runtime libraries. dell 403} cat z.c #include "stdio.h" double x, y, z; main () { x = 1234.33; printf("x %lf (1234.33) 0x%08lX\n", x , x); y = 4444.2; printf("y %lf (4444.2) 0x%08lX\n", y , y); z = x * y; printf("z = x * y, %lf %lf %lf\n", x , y, z); z = x / y; printf("z = x / y, %lf %lf %lf\n", x , y, z); } dell 404} cat z.s .file "z.c" gcc2_compiled.: .section ".rodata" .align 2 .LC1: .string "x %lf (1234.33) 0x%08lX\n" .align 2 .LC3: .string "y %lf (4444.2) 0x%08lX\n" .align 2 .LC4: .string "z = x * y, %lf %lf %lf\n" .align 2 .LC5: .string "z = x / y, %lf %lf %lf\n" .align 3 .LC0: .long 0x40934951 .long 0xeb851eb8 .align 3 .LC2: .long 0x40b15c33 .long 0x33333333 .section ".text" .align 2 .globl main .type main,@function main: stwu 1,-16(1) mflr 0 stw 31,12(1) stw 0,20(1) mr 31,1 lis 9,x@ha lis 11,.LC0@ha lfd 0,.LC0@l(11) stfd 0,x@l(9) lis 9,x@ha lis 11,x@ha lis 10,.LC1@ha la 3,.LC1@l(10) lfd 1,x@l(9) lfd 2,x@l(11) creqv 6,6,6 bl printf lis 9,y@ha lis 11,.LC2@ha lfd 0,.LC2@l(11) stfd 0,y@l(9) lis 9,y@ha lis 11,y@ha lis 10,.LC3@ha la 3,.LC3@l(10) lfd 1,y@l(9) lfd 2,y@l(11) creqv 6,6,6 bl printf lis 9,z@ha lis 11,x@ha lis 10,y@ha lfd 0,x@l(11) lfd 13,y@l(10) fmul 0,0,13 stfd 0,z@l(9) lis 9,x@ha lis 11,y@ha lis 10,z@ha lis 8,.LC4@ha la 3,.LC4@l(8) lfd 1,x@l(9) lfd 2,y@l(11) lfd 3,z@l(10) creqv 6,6,6 bl printf lis 9,z@ha lis 11,x@ha lis 10,y@ha lfd 0,x@l(11) lfd 13,y@l(10) fdiv 0,0,13 stfd 0,z@l(9) lis 9,x@ha lis 11,y@ha lis 10,z@ha lis 8,.LC5@ha la 3,.LC5@l(8) lfd 1,x@l(9) lfd 2,y@l(11) lfd 3,z@l(10) creqv 6,6,6 bl printf .L2: lwz 11,0(1) lwz 0,4(11) mtlr 0 lwz 31,-4(11) mr 1,11 blr .Lfe1: .size main,.Lfe1-main .comm x,8,8 .comm y,8,8 .comm z,8,8 .ident "GCC: (GNU) 2.95.2 19991024 (release)" On the target: > ./a.out x nan (1234.33) 0x00000000 y 0.000000 (4444.2) 0x1003FBCC z = x * y, 0.000000 0.000000 0.000000 z = x / y, 0.000000 0.000000 0.000000 The expected results should look something like: dell 420} ./a.out x 1234.330000 (1234.33) 0xEB851EB8 y 4444.200000 (4444.2) 0x33333333 z = x * y, 1234.330000 4444.200000 5485609.386000 z = x / y, 1234.330000 4444.200000 0.277740 We aren't even close to reasonable answers yet. ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/