sync headers with glibc

1 files changed, 140 insertions, 4 deletions

diff --git a/libc/sysdeps/linux/powerpc/sys/ucontext.h b/libc/sysdeps/linux/powerpc/sys/ucontext.h
index 07f0933ff..9eb50aa96 100644
--- a/libc/sysdeps/linux/powerpc/sys/ucontext.h
+++ b/libc/sysdeps/linux/powerpc/sys/ucontext.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
+/* Copyright (C) 1998, 1999, 2002, 2004, 2005 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -26,7 +26,110 @@
    included in <signal.h>.  */
 #include <bits/sigcontext.h>
 
-typedef struct sigcontext mcontext_t;
+#if __WORDSIZE == 32
+
+/* Number of general registers.  */
+# define NGREG	48
+
+/* Container for all general registers.  */
+typedef unsigned long gregset_t[NGREG];
+
+/* Container for floating-point registers and status */
+typedef struct _libc_fpstate
+{
+	double fpregs[32];
+	double fpscr;
+	unsigned int _pad[2];
+} fpregset_t;
+
+/* Container for Altivec/VMX registers and status.
+   Needs to be aligned on a 16-byte boundary. */
+typedef struct _libc_vrstate
+{
+	unsigned int vrregs[32][4];
+	unsigned int vrsave;
+	unsigned int _pad[2];
+	unsigned int vscr;
+} vrregset_t;
+
+/* Context to describe whole processor state.  */
+typedef struct
+{
+	gregset_t gregs;
+	fpregset_t fpregs;
+	vrregset_t vrregs __attribute__((__aligned__(16)));
+} mcontext_t;
+
+#else
+
+/* For 64-bit kernels with Altivec support, a machine context is exactly 
+ * a sigcontext.  For older kernel (without Altivec) the sigcontext matches 
+ * the mcontext upto but not including the v_regs field.  For kernels that 
+ * don't AT_HWCAP or return AT_HWCAP without PPC_FEATURE_HAS_ALTIVEC the 
+ * v_regs field may not exit and should not be referenced.  The v_regd field
+ * can be refernced safely only after verifying that PPC_FEATURE_HAS_ALTIVEC
+ * is set in AT_HWCAP.  */
+    
+/* Number of general registers.  */
+# define NGREG	48	/* includes r0-r31, nip, msr, lr, etc.   */
+# define NFPREG	33	/* includes fp0-fp31 &fpscr.  */
+# define NVRREG	34	/* includes v0-v31, vscr, & vrsave in split vectors */
+
+typedef unsigned long gregset_t[NGREG];
+typedef double fpregset_t[NFPREG];
+
+/* Container for Altivec/VMX Vector Status and Control Register.  Only 32-bits
+   but can only be copied to/from a 128-bit vector register.  So we allocated 
+   a whole quadword speedup save/restore.  */
+typedef struct _libc_vscr
+{
+	unsigned int __pad[3];
+	unsigned int vscr_word;
+} vscr_t;
+
+/* Container for Altivec/VMX registers and status.
+   Must to be aligned on a 16-byte boundary. */
+typedef struct _libc_vrstate
+{
+	unsigned int	vrregs[32][4];
+	vscr_t		vscr;
+	unsigned int	vrsave;
+	unsigned int	__pad[3];
+} vrregset_t  __attribute__((__aligned__(16)));
+
+typedef struct {
+	unsigned long	__unused[4];
+	int		signal;
+	int		__pad0;
+	unsigned long	handler;
+	unsigned long	oldmask;
+	struct pt_regs	*regs;
+	gregset_t	gp_regs;
+	fpregset_t	fp_regs;
+/*
+ * To maintain compatibility with current implementations the sigcontext is 
+ * extended by appending a pointer (v_regs) to a quadword type (elf_vrreg_t) 
+ * followed by an unstructured (vmx_reserve) field of 69 doublewords.  This 
+ * allows the array of vector registers to be quadword aligned independent of 
+ * the alignment of the containing sigcontext or ucontext. It is the 
+ * responsibility of the code setting the sigcontext to set this pointer to 
+ * either NULL (if this processor does not support the VMX feature) or the 
+ * address of the first quadword within the allocated (vmx_reserve) area.
+ *
+ * The pointer (v_regs) of vector type (elf_vrreg_t) is essentually  
+ * an array of 34 quadword entries.  The entries with 
+ * indexes 0-31 contain the corresponding vector registers.  The entry with 
+ * index 32 contains the vscr as the last word (offset 12) within the 
+ * quadword.  This allows the vscr to be stored as either a quadword (since 
+ * it must be copied via a vector register to/from storage) or as a word.  
+ * The entry with index 33 contains the vrsave as the first word (offset 0) 
+ * within the quadword.
+ */
+	vrregset_t	*v_regs;
+	long		vmx_reserve[NVRREG+NVRREG+1];
+} mcontext_t;
+
+#endif
 
 /* Userlevel context.  */
 typedef struct ucontext
@@ -34,8 +137,41 @@ typedef struct ucontext
     unsigned long int uc_flags;
     struct ucontext *uc_link;
     stack_t uc_stack;
-    mcontext_t uc_mcontext;
-    __sigset_t uc_sigmask;
+#if __WORDSIZE == 32
+    /*
+     * These fields are set up this way to maximize source and
+     * binary compatibility with code written for the old
+     * ucontext_t definition, which didn't include space for the
+     * registers.
+     *
+     * Different versions of the kernel have stored the registers on
+     * signal delivery at different offsets from the ucontext struct.
+     * Programs should thus use the uc_mcontext.uc_regs pointer to
+     * find where the registers are actually stored.  The registers
+     * will be stored within the ucontext_t struct but not necessarily
+     * at a fixed address.  As a side-effect, this lets us achieve
+     * 16-byte alignment for the register storage space if the
+     * Altivec registers are to be saved, without requiring 16-byte
+     * alignment on the whole ucontext_t.
+     *
+     * The uc_mcontext.regs field is included for source compatibility
+     * with programs written against the older ucontext_t definition,
+     * and its name should therefore not change.  The uc_pad field
+     * is for binary compatibility with programs compiled against the
+     * old ucontext_t; it ensures that uc_mcontext.regs and uc_sigmask
+     * are at the same offset as previously.
+     */
+    int uc_pad[7];
+    union uc_regs_ptr {
+      struct pt_regs *regs;
+      mcontext_t *uc_regs;
+    } uc_mcontext;
+    sigset_t    uc_sigmask;
+    char uc_reg_space[sizeof(mcontext_t) + 12];  /* last for extensibility */
+#else /* 64-bit */
+    sigset_t    uc_sigmask;
+    mcontext_t  uc_mcontext;  /* last for extensibility */
+#endif
   } ucontext_t;
 
 #endif /* sys/ucontext.h */