Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / x86 / math-emu / reg_constant.c

diff --git a/kernel/arch/x86/math-emu/reg_constant.c b/kernel/arch/x86/math-emu/reg_constant.c
new file mode 100644 (file)
index 0000000..0054835
--- /dev/null
+++ b/kernel/arch/x86/math-emu/reg_constant.c
@@ -0,0 +1,117 @@
+/*---------------------------------------------------------------------------+
+ |  reg_constant.c                                                           |
+ |                                                                           |
+ | All of the constant FPU_REGs                                              |
+ |                                                                           |
+ | Copyright (C) 1992,1993,1994,1997                                         |
+ |                     W. Metzenthen, 22 Parker St, Ormond, Vic 3163,        |
+ |                     Australia.  E-mail   billm@suburbia.net               |
+ |                                                                           |
+ |                                                                           |
+ +---------------------------------------------------------------------------*/
+
+#include "fpu_system.h"
+#include "fpu_emu.h"
+#include "status_w.h"
+#include "reg_constant.h"
+#include "control_w.h"
+
+#define MAKE_REG(s, e, l, h) { l, h, \
+               ((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) }
+
+FPU_REG const CONST_1 = MAKE_REG(POS, 0, 0x00000000, 0x80000000);
+#if 0
+FPU_REG const CONST_2 = MAKE_REG(POS, 1, 0x00000000, 0x80000000);
+FPU_REG const CONST_HALF = MAKE_REG(POS, -1, 0x00000000, 0x80000000);
+#endif /*  0  */
+static FPU_REG const CONST_L2T = MAKE_REG(POS, 1, 0xcd1b8afe, 0xd49a784b);
+static FPU_REG const CONST_L2E = MAKE_REG(POS, 0, 0x5c17f0bc, 0xb8aa3b29);
+FPU_REG const CONST_PI = MAKE_REG(POS, 1, 0x2168c235, 0xc90fdaa2);
+FPU_REG const CONST_PI2 = MAKE_REG(POS, 0, 0x2168c235, 0xc90fdaa2);
+FPU_REG const CONST_PI4 = MAKE_REG(POS, -1, 0x2168c235, 0xc90fdaa2);
+static FPU_REG const CONST_LG2 = MAKE_REG(POS, -2, 0xfbcff799, 0x9a209a84);
+static FPU_REG const CONST_LN2 = MAKE_REG(POS, -1, 0xd1cf79ac, 0xb17217f7);
+
+/* Extra bits to take pi/2 to more than 128 bits precision. */
+FPU_REG const CONST_PI2extra = MAKE_REG(NEG, -66,
+                                       0xfc8f8cbb, 0xece675d1);
+
+/* Only the sign (and tag) is used in internal zeroes */
+FPU_REG const CONST_Z = MAKE_REG(POS, EXP_UNDER, 0x0, 0x0);
+
+/* Only the sign and significand (and tag) are used in internal NaNs */
+/* The 80486 never generates one of these
+FPU_REG const CONST_SNAN = MAKE_REG(POS, EXP_OVER, 0x00000001, 0x80000000);
+ */
+/* This is the real indefinite QNaN */
+FPU_REG const CONST_QNaN = MAKE_REG(NEG, EXP_OVER, 0x00000000, 0xC0000000);
+
+/* Only the sign (and tag) is used in internal infinities */
+FPU_REG const CONST_INF = MAKE_REG(POS, EXP_OVER, 0x00000000, 0x80000000);
+
+static void fld_const(FPU_REG const * c, int adj, u_char tag)
+{
+       FPU_REG *st_new_ptr;
+
+       if (STACK_OVERFLOW) {
+               FPU_stack_overflow();
+               return;
+       }
+       push();
+       reg_copy(c, st_new_ptr);
+       st_new_ptr->sigl += adj;        /* For all our fldxxx constants, we don't need to
+                                          borrow or carry. */
+       FPU_settag0(tag);
+       clear_C1();
+}
+
+/* A fast way to find out whether x is one of RC_DOWN or RC_CHOP
+   (and not one of RC_RND or RC_UP).
+   */
+#define DOWN_OR_CHOP(x)  (x & RC_DOWN)
+
+static void fld1(int rc)
+{
+       fld_const(&CONST_1, 0, TAG_Valid);
+}
+
+static void fldl2t(int rc)
+{
+       fld_const(&CONST_L2T, (rc == RC_UP) ? 1 : 0, TAG_Valid);
+}
+
+static void fldl2e(int rc)
+{
+       fld_const(&CONST_L2E, DOWN_OR_CHOP(rc) ? -1 : 0, TAG_Valid);
+}
+
+static void fldpi(int rc)
+{
+       fld_const(&CONST_PI, DOWN_OR_CHOP(rc) ? -1 : 0, TAG_Valid);
+}
+
+static void fldlg2(int rc)
+{
+       fld_const(&CONST_LG2, DOWN_OR_CHOP(rc) ? -1 : 0, TAG_Valid);
+}
+
+static void fldln2(int rc)
+{
+       fld_const(&CONST_LN2, DOWN_OR_CHOP(rc) ? -1 : 0, TAG_Valid);
+}
+
+static void fldz(int rc)
+{
+       fld_const(&CONST_Z, 0, TAG_Zero);
+}
+
+typedef void (*FUNC_RC) (int);
+
+static FUNC_RC constants_table[] = {
+       fld1, fldl2t, fldl2e, fldpi, fldlg2, fldln2, fldz, (FUNC_RC) FPU_illegal
+};
+
+void fconst(void)
+{
+       (constants_table[FPU_rm]) (control_word & CW_RC);
+}