i386: move math-emu

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

1 files changed, 143 insertions, 0 deletions

diff --git a/arch/x86/math-emu/fpu_etc.c b/arch/x86/math-emu/fpu_etc.c
new file mode 100644
index 0000000..e3b5d46
--- /dev/null
+++ b/arch/x86/math-emu/fpu_etc.c
@@ -0,0 +1,143 @@
+/*---------------------------------------------------------------------------+
+ |  fpu_etc.c                                                                |
+ |                                                                           |
+ | Implement a few FPU 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 "reg_constant.h"
+
+
+static void fchs(FPU_REG *st0_ptr, u_char st0tag)
+{
+  if ( st0tag ^ TAG_Empty )
+    {
+      signbyte(st0_ptr) ^= SIGN_NEG;
+      clear_C1();
+    }
+  else
+    FPU_stack_underflow();
+}
+
+
+static void fabs(FPU_REG *st0_ptr, u_char st0tag)
+{
+  if ( st0tag ^ TAG_Empty )
+    {
+      setpositive(st0_ptr);
+      clear_C1();
+    }
+  else
+    FPU_stack_underflow();
+}
+
+
+static void ftst_(FPU_REG *st0_ptr, u_char st0tag)
+{
+  switch (st0tag)
+    {
+    case TAG_Zero:
+      setcc(SW_C3);
+      break;
+    case TAG_Valid:
+      if (getsign(st0_ptr) == SIGN_POS)
+        setcc(0);
+      else
+        setcc(SW_C0);
+      break;
+    case TAG_Special:
+      switch ( FPU_Special(st0_ptr) )
+	{
+	case TW_Denormal:
+	  if (getsign(st0_ptr) == SIGN_POS)
+	    setcc(0);
+	  else
+	    setcc(SW_C0);
+	  if ( denormal_operand() < 0 )
+	    {
+#ifdef PECULIAR_486
+	      /* This is weird! */
+	      if (getsign(st0_ptr) == SIGN_POS)
+		setcc(SW_C3);
+#endif /* PECULIAR_486 */
+	      return;
+	    }
+	  break;
+	case TW_NaN:
+	  setcc(SW_C0|SW_C2|SW_C3);   /* Operand is not comparable */ 
+	  EXCEPTION(EX_Invalid);
+	  break;
+	case TW_Infinity:
+	  if (getsign(st0_ptr) == SIGN_POS)
+	    setcc(0);
+	  else
+	    setcc(SW_C0);
+	  break;
+	default:
+	  setcc(SW_C0|SW_C2|SW_C3);   /* Operand is not comparable */ 
+	  EXCEPTION(EX_INTERNAL|0x14);
+	  break;
+	}
+      break;
+    case TAG_Empty:
+      setcc(SW_C0|SW_C2|SW_C3);
+      EXCEPTION(EX_StackUnder);
+      break;
+    }
+}
+
+
+static void fxam(FPU_REG *st0_ptr, u_char st0tag)
+{
+  int c = 0;
+  switch (st0tag)
+    {
+    case TAG_Empty:
+      c = SW_C3|SW_C0;
+      break;
+    case TAG_Zero:
+      c = SW_C3;
+      break;
+    case TAG_Valid:
+      c = SW_C2;
+      break;
+    case TAG_Special:
+      switch ( FPU_Special(st0_ptr) )
+	{
+	case TW_Denormal:
+	  c = SW_C2|SW_C3;  /* Denormal */
+	  break;
+	case TW_NaN:
+	  /* We also use NaN for unsupported types. */
+	  if ( (st0_ptr->sigh & 0x80000000) && (exponent(st0_ptr) == EXP_OVER) )
+	    c = SW_C0;
+	  break;
+	case TW_Infinity:
+	  c = SW_C2|SW_C0;
+	  break;
+	}
+    }
+  if ( getsign(st0_ptr) == SIGN_NEG )
+    c |= SW_C1;
+  setcc(c);
+}
+
+
+static FUNC_ST0 const fp_etc_table[] = {
+  fchs, fabs, (FUNC_ST0)FPU_illegal, (FUNC_ST0)FPU_illegal,
+  ftst_, fxam, (FUNC_ST0)FPU_illegal, (FUNC_ST0)FPU_illegal
+};
+
+void FPU_etc(void)
+{
+  (fp_etc_table[FPU_rm])(&st(0), FPU_gettag0());
+}