patch-2.4.19 linux-2.4.19/arch/arm/nwfpe/fpa11.h

• Lines: 89
• Date: Fri Aug 2 17:39:42 2002
• Orig file: linux-2.4.18/arch/arm/nwfpe/fpa11.h
• Orig date: Sun Aug 12 11:13:59 2001

diff -urN linux-2.4.18/arch/arm/nwfpe/fpa11.h linux-2.4.19/arch/arm/nwfpe/fpa11.h
@@ -22,45 +22,67 @@
 #ifndef __FPA11_H__
 #define __FPA11_H__
 
-/* includes */
-#include "fpsr.h"		/* FP control and status register definitions */
-#include "softfloat.h"
+#define GET_FPA11() ((FPA11 *)(&current->thread.fpstate))
+
+/*
+ * The processes registers are always at the very top of the 8K
+ * stack+task struct.  Use the same method as 'current' uses to
+ * reach them.
+ */
+register unsigned int *user_registers asm("sl");
+
+#define GET_USERREG() (user_registers)
 
 /* Need task_struct */
 #include <linux/sched.h>
 
+/* includes */
+#include "fpsr.h"		/* FP control and status register definitions */
+#include "softfloat.h"
+
 #define		typeNone		0x00
 #define		typeSingle		0x01
 #define		typeDouble		0x02
 #define		typeExtended		0x03
 
+/*
+ * This must be no more and no less than 12 bytes.
+ */
 typedef union tagFPREG {
-   float32  fSingle;
-   float64  fDouble;
    floatx80 fExtended;
+   float64  fDouble;
+   float32  fSingle;
 } FPREG;
 
-/* FPA11 device model */
+/*
+ * FPA11 device model.
+ *
+ * This structure is exported to user space.  Do not re-order.
+ * Only add new stuff to the end, and do not change the size of
+ * any element.  Elements of this structure are used by user
+ * space, and must match struct user_fp in include/asm-arm/user.h.
+ * We include the byte offsets below for documentation purposes.
+ *
+ * The size of this structure and FPREG are checked by fpmodule.c
+ * on initialisation.  If the rules have been broken, NWFPE will
+ * not initialise.
+ */
 typedef struct tagFPA11 {
-  unsigned int *userRegisters;
-  FPREG fpreg[8];		/* 8 floating point registers */
-  FPSR fpsr;			/* floating point status register */
-  FPCR fpcr;			/* floating point control register */
-  unsigned char fType[8];	/* type of floating point value held in
-				   floating point registers.  One of none
-				   single, double or extended. */
-  int initflag;			/* this is special.  The kernel guarantees
-				   to set it to 0 when a thread is launched,
-				   so we can use it to detect whether this
-				   instance of the emulator needs to be
-				   initialised. */
+/*   0 */  FPREG fpreg[8];		/* 8 floating point registers */
+/*  96 */  FPSR fpsr;			/* floating point status register */
+/* 100 */  FPCR fpcr;			/* floating point control register */
+/* 104 */  unsigned char fType[8];	/* type of floating point value held in
+					   floating point registers.  One of none
+					   single, double or extended. */
+/* 112 */  int initflag;		/* this is special.  The kernel guarantees
+					   to set it to 0 when a thread is launched,
+					   so we can use it to detect whether this
+					   instance of the emulator needs to be
+					   initialised. */
 } FPA11;
 
 extern void resetFPA11(void);
 extern void SetRoundingMode(const unsigned int);
 extern void SetRoundingPrecision(const unsigned int);
 
-#define GET_FPA11() ((FPA11 *)(&current->thread.fpstate))
-#define GET_USERREG() (GET_FPA11()->userRegisters)
-
 #endif