Add the rt linux 4.1.3-rt3 as base

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

diff --git a/kernel/arch/x86/math-emu/fpu_aux.c b/kernel/arch/x86/math-emu/fpu_aux.c
new file mode 100644 (file)
index 0000000..dc8adad
--- /dev/null
+++ b/kernel/arch/x86/math-emu/fpu_aux.c
@@ -0,0 +1,196 @@
+/*---------------------------------------------------------------------------+
+ |  fpu_aux.c                                                                |
+ |                                                                           |
+ | Code to implement some of the FPU auxiliary instructions.                 |
+ |                                                                           |
+ | 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 "exception.h"
+#include "fpu_emu.h"
+#include "status_w.h"
+#include "control_w.h"
+
+static void fnop(void)
+{
+}
+
+static void fclex(void)
+{
+       partial_status &=
+           ~(SW_Backward | SW_Summary | SW_Stack_Fault | SW_Precision |
+             SW_Underflow | SW_Overflow | SW_Zero_Div | SW_Denorm_Op |
+             SW_Invalid);
+       no_ip_update = 1;
+}
+
+/* Needs to be externally visible */
+void finit_soft_fpu(struct i387_soft_struct *soft)
+{
+       struct address *oaddr, *iaddr;
+       memset(soft, 0, sizeof(*soft));
+       soft->cwd = 0x037f;
+       soft->swd = 0;
+       soft->ftop = 0; /* We don't keep top in the status word internally. */
+       soft->twd = 0xffff;
+       /* The behaviour is different from that detailed in
+          Section 15.1.6 of the Intel manual */
+       oaddr = (struct address *)&soft->foo;
+       oaddr->offset = 0;
+       oaddr->selector = 0;
+       iaddr = (struct address *)&soft->fip;
+       iaddr->offset = 0;
+       iaddr->selector = 0;
+       iaddr->opcode = 0;
+       soft->no_update = 1;
+}
+
+void finit(void)
+{
+       finit_soft_fpu(&current->thread.fpu.state->soft);
+}
+
+/*
+ * These are nops on the i387..
+ */
+#define feni fnop
+#define fdisi fnop
+#define fsetpm fnop
+
+static FUNC const finit_table[] = {
+       feni, fdisi, fclex, finit,
+       fsetpm, FPU_illegal, FPU_illegal, FPU_illegal
+};
+
+void finit_(void)
+{
+       (finit_table[FPU_rm]) ();
+}
+
+static void fstsw_ax(void)
+{
+       *(short *)&FPU_EAX = status_word();
+       no_ip_update = 1;
+}
+
+static FUNC const fstsw_table[] = {
+       fstsw_ax, FPU_illegal, FPU_illegal, FPU_illegal,
+       FPU_illegal, FPU_illegal, FPU_illegal, FPU_illegal
+};
+
+void fstsw_(void)
+{
+       (fstsw_table[FPU_rm]) ();
+}
+
+static FUNC const fp_nop_table[] = {
+       fnop, FPU_illegal, FPU_illegal, FPU_illegal,
+       FPU_illegal, FPU_illegal, FPU_illegal, FPU_illegal
+};
+
+void fp_nop(void)
+{
+       (fp_nop_table[FPU_rm]) ();
+}
+
+void fld_i_(void)
+{
+       FPU_REG *st_new_ptr;
+       int i;
+       u_char tag;
+
+       if (STACK_OVERFLOW) {
+               FPU_stack_overflow();
+               return;
+       }
+
+       /* fld st(i) */
+       i = FPU_rm;
+       if (NOT_EMPTY(i)) {
+               reg_copy(&st(i), st_new_ptr);
+               tag = FPU_gettagi(i);
+               push();
+               FPU_settag0(tag);
+       } else {
+               if (control_word & CW_Invalid) {
+                       /* The masked response */
+                       FPU_stack_underflow();
+               } else
+                       EXCEPTION(EX_StackUnder);
+       }
+
+}
+
+void fxch_i(void)
+{
+       /* fxch st(i) */
+       FPU_REG t;
+       int i = FPU_rm;
+       FPU_REG *st0_ptr = &st(0), *sti_ptr = &st(i);
+       long tag_word = fpu_tag_word;
+       int regnr = top & 7, regnri = ((regnr + i) & 7);
+       u_char st0_tag = (tag_word >> (regnr * 2)) & 3;
+       u_char sti_tag = (tag_word >> (regnri * 2)) & 3;
+
+       if (st0_tag == TAG_Empty) {
+               if (sti_tag == TAG_Empty) {
+                       FPU_stack_underflow();
+                       FPU_stack_underflow_i(i);
+                       return;
+               }
+               if (control_word & CW_Invalid) {
+                       /* Masked response */
+                       FPU_copy_to_reg0(sti_ptr, sti_tag);
+               }
+               FPU_stack_underflow_i(i);
+               return;
+       }
+       if (sti_tag == TAG_Empty) {
+               if (control_word & CW_Invalid) {
+                       /* Masked response */
+                       FPU_copy_to_regi(st0_ptr, st0_tag, i);
+               }
+               FPU_stack_underflow();
+               return;
+       }
+       clear_C1();
+
+       reg_copy(st0_ptr, &t);
+       reg_copy(sti_ptr, st0_ptr);
+       reg_copy(&t, sti_ptr);
+
+       tag_word &= ~(3 << (regnr * 2)) & ~(3 << (regnri * 2));
+       tag_word |= (sti_tag << (regnr * 2)) | (st0_tag << (regnri * 2));
+       fpu_tag_word = tag_word;
+}
+
+void ffree_(void)
+{
+       /* ffree st(i) */
+       FPU_settagi(FPU_rm, TAG_Empty);
+}
+
+void ffreep(void)
+{
+       /* ffree st(i) + pop - unofficial code */
+       FPU_settagi(FPU_rm, TAG_Empty);
+       FPU_pop();
+}
+
+void fst_i_(void)
+{
+       /* fst st(i) */
+       FPU_copy_to_regi(&st(0), FPU_gettag0(), FPU_rm);
+}
+
+void fstp_i(void)
+{
+       /* fstp st(i) */
+       FPU_copy_to_regi(&st(0), FPU_gettag0(), FPU_rm);
+       FPU_pop();
+}