i386: move math-emu

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 204 insertions, 0 deletions

diff --git a/arch/x86/math-emu/fpu_aux.c b/arch/x86/math-emu/fpu_aux.c
new file mode 100644
index 00000000000..20886cfb9f7
--- /dev/null
+++ b/arch/x86/math-emu/fpu_aux.c
@@ -0,0 +1,204 @@
+/*---------------------------------------------------------------------------+
+ |  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(void)
+{
+  control_word = 0x037f;
+  partial_status = 0;
+  top = 0;            /* We don't keep top in the status word internally. */
+  fpu_tag_word = 0xffff;
+  /* The behaviour is different from that detailed in
+     Section 15.1.6 of the Intel manual */
+  operand_address.offset = 0;
+  operand_address.selector = 0;
+  instruction_address.offset = 0;
+  instruction_address.selector = 0;
+  instruction_address.opcode = 0;
+  no_ip_update = 1;
+}
+
+/*
+ * 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();
+}
+