| /* |
| * Test DIEBR and DIDBR instructions. |
| * |
| * Most inputs were discovered by fuzzing and exercise various corner cases in |
| * the helpers. |
| * |
| * SPDX-License-Identifier: GPL-2.0-or-later |
| */ |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <asm/ucontext.h> |
| |
| static void sigfpe_handler(int sig, siginfo_t *info, void *puc) |
| { |
| struct ucontext *uc = puc; |
| unsigned short *xr_insn; |
| int r; |
| |
| xr_insn = (unsigned short *)(uc->uc_mcontext.regs.psw.addr - 6); |
| r = *xr_insn & 0xf; |
| uc->uc_mcontext.regs.gprs[r] = sig; |
| } |
| |
| #define DIVIDE_TO_INTEGER(name, floatN) \ |
| static inline __attribute__((__always_inline__)) int \ |
| name(floatN *r1, floatN r2, floatN *r3, int m4, int *sig) \ |
| { \ |
| int cc; \ |
| \ |
| asm(/* Make the initial CC predictable for suppression tests */ \ |
| "xr %[sig],%[sig]\n" \ |
| #name " %[r1],%[r3],%[r2],%[m4]\n" \ |
| "ipm %[cc]\n" \ |
| "srl %[cc],28" \ |
| /* \ |
| * Use earlyclobbers to prevent the compiler from reusing floating \ |
| * point registers. This instruction doesn't like it. \ |
| */ \ |
| : [r1] "+&f" (*r1), [r3] "+&f" (*r3), [sig] "=r" (*sig), [cc] "=d" (cc)\ |
| : [r2] "f" (r2), [m4] "i" (m4) \ |
| : "cc"); \ |
| \ |
| return cc; \ |
| } |
| |
| DIVIDE_TO_INTEGER(diebr, float) |
| DIVIDE_TO_INTEGER(didbr, double) |
| |
| #define TEST_DIVIDE_TO_INTEGER(name, intN, int_fmt, floatN, float_fmt) \ |
| static inline __attribute__((__always_inline__)) int \ |
| test_ ## name(unsigned intN r1i, unsigned intN r2i, int m4, int fpc, \ |
| unsigned intN r1o, unsigned intN r3o, int cco, unsigned int fpco,\ |
| int sigo) \ |
| { \ |
| union { \ |
| floatN f; \ |
| unsigned intN i; \ |
| } r1, r2, r3; \ |
| int cc, err = 0, sig; \ |
| \ |
| r1.i = r1i; \ |
| r2.i = r2i; \ |
| r3.i = 0x12345678; \ |
| printf("[ RUN ] %" float_fmt "(0x%" int_fmt \ |
| ") / %" float_fmt "(0x%" int_fmt ")\n", r1.f, r1.i, r2.f, r2.i); \ |
| asm volatile("sfpc %[fpc]" : : [fpc] "r" (fpc)); \ |
| cc = name(&r1.f, r2.f, &r3.f, m4, &sig); \ |
| asm volatile("stfpc %[fpc]" : [fpc] "=Q" (fpc)); \ |
| if (r1.i != r1o) { \ |
| printf("[ FAILED ] remainder 0x%" int_fmt \ |
| " != expected 0x%" int_fmt "\n", r1.i, r1o); \ |
| err += 1; \ |
| } \ |
| if (r3.i != r3o) { \ |
| printf("[ FAILED ] quotient 0x%" int_fmt \ |
| " != expected 0x%" int_fmt "\n", r3.i, r3o); \ |
| err += 1; \ |
| } \ |
| if (cc != cco) { \ |
| printf("[ FAILED ] cc %d != expected %d\n", cc, cco); \ |
| err += 1; \ |
| } \ |
| if (fpc != fpco) { \ |
| printf("[ FAILED ] fpc 0x%x != expected 0x%x\n", fpc, fpco); \ |
| err += 1; \ |
| } \ |
| if (sig != sigo) { \ |
| printf("[ FAILED ] signal 0x%x != expected 0x%x\n", sig, sigo); \ |
| err += 1; \ |
| } \ |
| \ |
| return err; \ |
| } |
| |
| TEST_DIVIDE_TO_INTEGER(diebr, int, "x", float, "f") |
| TEST_DIVIDE_TO_INTEGER(didbr, long, "lx", double, "lf") |
| |
| int main(void) |
| { |
| struct sigaction act = { |
| .sa_sigaction = sigfpe_handler, |
| .sa_flags = SA_SIGINFO, |
| }; |
| int err = 0; |
| |
| /* Set up SIG handler */ |
| if (sigaction(SIGFPE, &act, NULL)) { |
| printf("[ FAILED ] sigaction(SIGFPE) failed\n"); |
| return EXIT_FAILURE; |
| } |
| |
| /* 451 / 460 */ |
| err += test_diebr(0x43e1f1f1, 0x43e61616, 7, 0, |
| 0x43e1f1f1, 0, 0, 0, 0); |
| |
| /* 480 / 0 */ |
| err += test_diebr(0x43f00000, 0, 0, 0, |
| 0x7fc00000, 0x7fc00000, 1, 0x800000, 0); |
| |
| /* QNaN / QNaN */ |
| err += test_diebr(0xffffffff, 0xffffffff, 0, 0, |
| 0xffffffff, 0xffffffff, 1, 0, 0); |
| |
| /* -2.08E-8 / -2.08E-8 */ |
| err += test_diebr(0xb2b2b2b2, 0xb2b2b2b2, 0, 0, |
| 0x80000000, 0x3f800000, 0, 0, 0); |
| |
| /* |
| * Test partial remainder without quotient scaling (cc2). |
| * |
| * a = 12401981 / 268435456 |
| * b = -5723991 / 72057594037927936 |
| * q = a / b = -3329131425038336 / 5723991 =~ -581610178.1 |
| * n = round(q, float32, nearest_even) = -581610176 |
| * r_precise = a - b * n = 189155 / 1125899906842624 |
| * r = round(r_precise, float32, nearest_even) = r_precise |
| */ |
| err += test_diebr(0x3d3d3d3d, 0xaeaeaeae, 0, 0, |
| 0x2f38b8c0, 0xce0aaaab, 2, 0, 0); |
| |
| /* 1.07E-31 / 2.19 */ |
| err += test_diebr(0x0c0c0c0c, 0x400c0c0c, 6, 0, |
| 0xc00c0c0c, 0x3f800000, 0, 0x80000, 0); |
| |
| /* |
| * Test partial remainder with quotient scaling (cc3). |
| * |
| * a = 298343530578310714772108083200 |
| * b = -592137/10384593717069655257060992658440192 |
| * q = a / b |
| * = -1032725451057301340137043014721780674141077289604872315653324800 / |
| * 197379 |
| * =~ -5232195173029052432817285601415452880707052369324357280426.6 |
| * n = round(q, float32, nearest_even) |
| * = -5232194943010009439437691768433469154159343131709361094656 |
| * n / 2^192 = -6992213 / 8388608 |
| * r_precise = a - b * n = 13115851209189604982784 |
| * r = round(r_precise, float32, nearest_even) = r_precise |
| */ |
| err += test_diebr(0x7070ffff, 0x90909090, 0, 0, |
| 0x6431c0c0, 0xbf5562aa, 3, 0, 0); |
| |
| /* |
| * Test large, but representable quotient. |
| * |
| * a = -12040119 / 549755813888 |
| * b = 1 / 38685626227668133590597632 |
| * q = a / b = -847248053779631702016 |
| * n = round(q, float32, to_odd) = q |
| * r_precise = a - b * n = -0 |
| * r = round(r_precise, float32, nearest_even) = -0 |
| */ |
| err += test_diebr(0xb7b7b7b7, 0x15000000, 7, 0, |
| 0x80000000, 0xe237b7b7, 0, 0, 0); |
| |
| /* 0 / 0 */ |
| err += test_diebr(0, 0, 1, 0, |
| 0x7fc00000, 0x7fc00000, 1, 0x800000, 0); |
| |
| /* 4.3E-33 / -2.08E-8 with SIGFPE */ |
| err += test_diebr(0x09b2b2b2, 0xb2b2b2b2, 0, 0xfc000007, |
| 0xb2b2b2b1, 0xbf800000, 0, 0xfc000807, SIGFPE); |
| |
| /* |
| * Test tiny remainder scaling when FPC Underflow Mask is set. |
| * |
| * 1.19E-39 / -1.28E-9 = { r = 1.19E-39 * 2^192, n = -0 } |
| */ |
| err += test_diebr(0x000d0100, 0xb0b0b0b0, 6, 0xfc000000, |
| 0x5ed01000, 0x80000000, 0, 0xfc001000, SIGFPE); |
| |
| /* |
| * Test "inexact and incremented" DXC. |
| * |
| * a = 53555504 |
| * b = -520849213389117849600 |
| * q = a / b = -3347219 / 32553075836819865600 |
| * n = round(q, float32, to_odd) = -1 |
| * r_precise = a - b * n = -520849213389064294096 |
| * r = round(r_precise, float32, to_odd) = -520849213389117849600 |
| * abs(r) - abs(r_precise) = 53555504 |
| */ |
| err += test_diebr(0x4c4c4c4c, 0xe1e1e1e1, 0, 0xfc000007, |
| 0xe1e1e1e1, 0xbf800000, 0, 0xfc000c07, SIGFPE); |
| |
| /* 0 / 0 with SIGFPE */ |
| err += test_diebr(0, 0, 0, 0xfc000007, |
| 0, 0x12345678, 0, 0xfc008007, SIGFPE); |
| |
| /* 5.76E-16 / 5.39E+34 */ |
| err += test_diebr(0x26262626, 0x79262626, 6, 0, |
| 0xf9262626, 0x3f800000, 0, 0x80000, 0); |
| |
| /* -4.97E+17 / 2.03E-38 */ |
| err += test_diebr(0xdcdcdcdc, 0x00dcdcdc, 7, 0xfc000000, |
| 0x80000000, 0xbb800000, 1, 0xfc000000, 0); |
| |
| /* -1.23E+17 / SNaN */ |
| err += test_diebr(0xdbdb240b, 0xffac73ff, 4, 0, |
| 0xffec73ff, 0xffec73ff, 1, 0x800000, 0); |
| |
| /* 2.34E-38 / 3.27E-33 with SIGFPE */ |
| err += test_diebr(0x00ff0987, 0x0987c6f6, 6, 0x08000000, |
| 0x8987c6b6, 0x3f800000, 0, 0x8000800, SIGFPE); |
| |
| /* -5.93E+11 / -2.7E+4 */ |
| err += test_diebr(0xd30a0040, 0xc6d30a00, 0, 0xc4000000, |
| 0xc74a4400, 0x4ba766c6, 2, 0xc4000000, 0); |
| |
| /* 9.86E-32 / -inf */ |
| err += test_diebr(0x0c000029, 0xff800000, 0, 0, |
| 0xc000029, 0x80000000, 0, 0, 0); |
| |
| /* QNaN / SNaN */ |
| err += test_diebr(0xffff94ff, 0xff94ff24, 4, 7, |
| 0xffd4ff24, 0xffd4ff24, 1, 0x800007, 0); |
| |
| /* 2.8E-43 / -inf */ |
| err += test_diebr(0x000000c8, 0xff800000, 0, 0x7c000007, |
| 0x000000c8, 0x80000000, 0, 0x7c000007, 0); |
| |
| /* -1.7E+38 / -inf */ |
| err += test_diebr(0xff00003d, 0xff800000, 0, 0, |
| 0xff00003d, 0, 0, 0, 0); |
| |
| /* 1.94E-304 / 1.94E-304 */ |
| err += test_didbr(0x00e100e100e100e1, 0x00e100e100e100e1, 0, 1, |
| 0, 0x3ff0000000000000, 0, 1, 0); |
| |
| /* 4.82E-299 / 5.29E-308 */ |
| err += test_didbr(0x0200230200230200, 0x0023020023020023, 0, 0, |
| 0x8001a017d247b3f4, 0x41cb2aa05f000000, 0, 0, 0); |
| |
| /* -1.38E-75 / -3.77E+208 */ |
| err += test_didbr(0xb063eb3d63b063eb, 0xeb3d63b063eb3d63, 3, 0xe8000000, |
| 0x6b3d63b063eb3d63, 0x3ff0000000000000, 0, 0xe8000c00, |
| SIGFPE); |
| |
| /* 4.78E-299 / 6.88E-315 */ |
| err += test_didbr(0x0200000000000000, 0x0000000053020000, 0, 0, |
| 0x8000000020820000, 0x4338ac20dd47c6c1, 0, 0, 0); |
| |
| return err ? EXIT_FAILURE : EXIT_SUCCESS; |
| } |
