Update.

2003-06-17  Paul Mackerras  <paulus@samba.org>

	* sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext.S: New file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S: New file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext.S: New file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext.S: New file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/ucontext_i.h: New file.
	* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h: Adjust.

6 files changed, 688 insertions, 5 deletions

diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext.S
new file mode 100644
index 0000000000..9405d12cfb
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext.S
@@ -0,0 +1,126 @@
+/* Save current context.
+   Copyright (C) 2002 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
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+
+#define __ASSEMBLY__
+#include <asm/ptrace.h>
+#include "ucontext_i.h"
+
+ENTRY(__getcontext)
+	stw	r0,_UC_GREGS+(PT_R0*4)(r3)
+	stw	r1,_UC_GREGS+(PT_R1*4)(r3)
+	mflr	r0
+	stwu	r1,-16(r1)
+	stw	r0,20(r1)
+	stw	r0,_UC_GREGS+(PT_LNK*4)(r3)
+	stw	r0,_UC_GREGS+(PT_NIP*4)(r3)
+	stw	r2,_UC_GREGS+(PT_R2*4)(r3)
+	stw	r4,_UC_GREGS+(PT_R4*4)(r3)
+	stw	r5,_UC_GREGS+(PT_R5*4)(r3)
+	stw	r6,_UC_GREGS+(PT_R6*4)(r3)
+	stw	r7,_UC_GREGS+(PT_R7*4)(r3)
+	stw	r8,_UC_GREGS+(PT_R8*4)(r3)
+	stw	r9,_UC_GREGS+(PT_R9*4)(r3)
+	stw	r10,_UC_GREGS+(PT_R10*4)(r3)
+	stw	r11,_UC_GREGS+(PT_R11*4)(r3)
+	stw	r12,_UC_GREGS+(PT_R12*4)(r3)
+	stw	r13,_UC_GREGS+(PT_R13*4)(r3)
+	stw	r14,_UC_GREGS+(PT_R14*4)(r3)
+	stw	r15,_UC_GREGS+(PT_R15*4)(r3)
+	stw	r16,_UC_GREGS+(PT_R16*4)(r3)
+	stw	r17,_UC_GREGS+(PT_R17*4)(r3)
+	stw	r18,_UC_GREGS+(PT_R18*4)(r3)
+	stw	r19,_UC_GREGS+(PT_R19*4)(r3)
+	stw	r20,_UC_GREGS+(PT_R20*4)(r3)
+	stw	r21,_UC_GREGS+(PT_R21*4)(r3)
+	stw	r22,_UC_GREGS+(PT_R22*4)(r3)
+	stw	r23,_UC_GREGS+(PT_R23*4)(r3)
+	stw	r24,_UC_GREGS+(PT_R24*4)(r3)
+	stw	r25,_UC_GREGS+(PT_R25*4)(r3)
+	stw	r26,_UC_GREGS+(PT_R26*4)(r3)
+	stw	r27,_UC_GREGS+(PT_R27*4)(r3)
+	stw	r28,_UC_GREGS+(PT_R28*4)(r3)
+	stw	r29,_UC_GREGS+(PT_R29*4)(r3)
+	stw	r30,_UC_GREGS+(PT_R30*4)(r3)
+	stw	r31,_UC_GREGS+(PT_R31*4)(r3)
+	mfctr	r0
+	stw	r0,_UC_GREGS+(PT_CTR*4)(r3)
+	mfxer	r0
+	stw	r0,_UC_GREGS+(PT_XER*4)(r3)
+	mfcr	r0
+	stw	r0,_UC_GREGS+(PT_CCR*4)(r3)
+
+	/* Set the return value of getcontext to "success".  R3 is the only 
+	   register whose value is not preserved in the saved context.  */
+	li	r0,0
+	stw	r0,_UC_GREGS+(PT_R3*4)(r3)
+
+	/* Zero fill fields that can't be set in user state. */
+	stw	r0,_UC_GREGS+(PT_MSR*4)(r3)
+	stw	r0,_UC_GREGS+(PT_MQ*4)(r3)
+
+	/* Save the floating-point registers */
+	stfd	fp0,_UC_FREGS+(0*8)(r3)
+	stfd	fp1,_UC_FREGS+(1*8)(r3)
+	stfd	fp2,_UC_FREGS+(2*8)(r3)
+	stfd	fp3,_UC_FREGS+(3*8)(r3)
+	stfd	fp4,_UC_FREGS+(4*8)(r3)
+	stfd	fp5,_UC_FREGS+(5*8)(r3)
+	stfd	fp6,_UC_FREGS+(6*8)(r3)
+	stfd	fp7,_UC_FREGS+(7*8)(r3)
+	stfd	fp8,_UC_FREGS+(8*8)(r3)
+	stfd	fp9,_UC_FREGS+(9*8)(r3)
+	stfd	fp10,_UC_FREGS+(10*8)(r3)
+	stfd	fp11,_UC_FREGS+(11*8)(r3)
+	stfd	fp12,_UC_FREGS+(12*8)(r3)
+	stfd	fp13,_UC_FREGS+(13*8)(r3)
+	stfd	fp14,_UC_FREGS+(14*8)(r3)
+	stfd	fp15,_UC_FREGS+(15*8)(r3)
+	stfd	fp16,_UC_FREGS+(16*8)(r3)
+	stfd	fp17,_UC_FREGS+(17*8)(r3)
+	stfd	fp18,_UC_FREGS+(18*8)(r3)
+	stfd	fp19,_UC_FREGS+(19*8)(r3)
+	stfd	fp20,_UC_FREGS+(20*8)(r3)
+	stfd	fp21,_UC_FREGS+(21*8)(r3)
+	stfd	fp22,_UC_FREGS+(22*8)(r3)
+	stfd	fp23,_UC_FREGS+(23*8)(r3)
+	stfd	fp24,_UC_FREGS+(24*8)(r3)
+	stfd	fp25,_UC_FREGS+(25*8)(r3)
+	stfd	fp26,_UC_FREGS+(26*8)(r3)
+	stfd	fp27,_UC_FREGS+(27*8)(r3)
+	stfd	fp28,_UC_FREGS+(28*8)(r3)
+	stfd	fp29,_UC_FREGS+(29*8)(r3)
+	mffs	fp0
+	stfd	fp30,_UC_FREGS+(30*8)(r3)
+	stfd	fp31,_UC_FREGS+(31*8)(r3)
+	stfd	fp0,_UC_FREGS+(32*8)(r3)
+
+	addi	r5,r3,_UC_SIGMASK
+	li	r4,0
+	li	r3,SIG_BLOCK
+	bl	JUMPTARGET(sigprocmask)
+
+	lwz	r0,20(r1)
+	addi	r1,r1,16
+	mtlr	r0
+	blr
+PSEUDO_END(__getcontext)
+
+weak_alias(__getcontext, getcontext)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S
new file mode 100644
index 0000000000..b875aa5de0
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S
@@ -0,0 +1,105 @@
+/* Set up a context to call a function.
+   Copyright (C) 2002 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
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+
+#define __ASSEMBLY__
+#include <asm/ptrace.h>
+#include "ucontext_i.h"
+
+ENTRY(__makecontext)
+	/* Set up the first 7 args to the function in its registers */
+	stw	r6,_UC_GREGS+(PT_R3*4)(r3)
+	stw	r7,_UC_GREGS+(PT_R4*4)(r3)
+	stw	r8,_UC_GREGS+(PT_R5*4)(r3)
+	stw	r9,_UC_GREGS+(PT_R6*4)(r3)
+	stw	r10,_UC_GREGS+(PT_R7*4)(r3)
+	lwz	r8,8(r1)
+	lwz	r9,12(r1)
+	stw	r8,_UC_GREGS+(PT_R8*4)(r3)
+	stw	r9,_UC_GREGS+(PT_R9*4)(r3)
+
+	/* Set the NIP to the start of the function */
+	stw	r4,_UC_GREGS+(PT_NIP*4)(r3)
+
+	/* Set the function's r31 to ucp->uc_link for the exitcode below. */
+	lwz	r7,_UC_LINK(r3)
+	stw	r7,_UC_GREGS+(PT_R31*4)(r3)
+
+	/* Set the function's LR to point to the exitcode below. */
+#ifdef PIC
+	mflr	r0
+	bl	1f
+1:	mflr	r6
+	addi	r6,r6,L(exitcode)-1b
+	mtlr	r0
+#else
+	lis	r6,L(exitcode)@ha
+	addi	r6,r6,L(exitcode)@l
+#endif
+	stw	r6,_UC_GREGS+(PT_LNK*4)(r3)
+
+	/*
+	 * Set up the stack frame for the function.
+	 * If we have more than 5 args to the function (8 args to makecontext),
+	 * there will be some arguments on the stack which have to end up
+	 * in registers.  If there are more than 8 args to the function,
+	 * we have to copy (argc - 8) args from our stack to the functions'
+	 * stack (and allow space for them in the frame).
+	 */
+	lwz	r4,_UC_STACK_SP(r3)
+	lwz	r8,_UC_STACK_SIZE(r3)
+	add	r4,r4,r8
+	rlwinm	r4,r4,0,0,27	/* round down to 16-byte boundary */
+	addi	r7,r4,-16	/* stack frame for fn's caller */
+	cmpwi	r5,8
+	blt	2f		/* less than 8 args is easy */
+	lwz	r10,16(r1)
+	stw	r10,_UC_GREGS+(PT_R10*4)(r3)
+	beq	2f		/* if exactly 8 args */
+	subi	r9,r5,3
+	subi	r5,r5,8
+	rlwinm	r9,r9,2,0,27
+	subf	r7,r9,r4
+	mtctr	r5		/* copy the 9th and following args */
+	addi	r6,r1,16
+	addi	r8,r7,4
+3:	lwzu	r10,4(r6)
+	stwu	r10,4(r8)
+	bdnz	3b
+2:	stw	r7,_UC_GREGS+(PT_R1*4)(r3)
+	li	r6,0
+	stw	r6,0(r7)
+
+	blr
+
+/*
+ * If the function returns, it comes here.  We put ucp->uc_link in
+ * r31, which is a callee-saved register.  We have to continue with
+ * the context that r31 points to, or exit if it is 0.
+ */
+L(exitcode):
+	mr.	r3,r31
+	beq	4f
+	bl	JUMPTARGET(__setcontext)
+4:	bl	HIDDEN_JUMPTARGET(exit)
+	b	4b
+
+END(__makecontext)
+weak_alias(__makecontext, makecontext)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext.S
new file mode 100644
index 0000000000..1539b40f01
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext.S
@@ -0,0 +1,149 @@
+/* Jump to a new context.
+   Copyright (C) 2002 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
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+
+#define __ASSEMBLY__
+#include <asm/ptrace.h>
+#include "ucontext_i.h"
+
+ENTRY(__setcontext)
+	mflr	r0
+	stwu	r1,-16(r1)
+	stw	r0,20(r1)
+	stw	r31,12(r1)
+	mr	r31,r3
+
+	/*
+	 * If this ucontext refers to the point where we were interrupted
+	 * by a signal, we have to use the rt_sigreturn system call to
+	 * return to the context so we get both LR and CTR restored.
+	 *
+	 * Otherwise, the context we are restoring is either just after
+	 * a procedure call (getcontext/swapcontext) or at the beginning
+	 * of a procedure call (makecontext), so we don't need to restore
+	 * r0, xer, ctr.  We don't restore r2 since it will be used as
+	 * the TLS pointer.
+	 */
+	lwz	r0,_UC_GREGS+(PT_MSR*4)(r31)
+	cmpwi	r0,0
+	bne	L(do_sigret)
+
+	/* Restore the signal mask */
+	li	r5,0
+	addi	r4,r3,_UC_SIGMASK
+	li	r3,SIG_SETMASK
+	bl	JUMPTARGET(sigprocmask)
+	cmpwi	r3,0
+	bne	L(error_exit)
+
+	/* Restore the floating-point registers */
+	lfd	fp31,_UC_FREGS+(32*8)(r31)
+	lfd	fp0,_UC_FREGS+(0*8)(r31)
+	mtfsf	0xff,fp31
+	lfd	fp1,_UC_FREGS+(1*8)(r31)
+	lfd	fp2,_UC_FREGS+(2*8)(r31)
+	lfd	fp3,_UC_FREGS+(3*8)(r31)
+	lfd	fp4,_UC_FREGS+(4*8)(r31)
+	lfd	fp5,_UC_FREGS+(5*8)(r31)
+	lfd	fp6,_UC_FREGS+(6*8)(r31)
+	lfd	fp7,_UC_FREGS+(7*8)(r31)
+	lfd	fp8,_UC_FREGS+(8*8)(r31)
+	lfd	fp9,_UC_FREGS+(9*8)(r31)
+	lfd	fp10,_UC_FREGS+(10*8)(r31)
+	lfd	fp11,_UC_FREGS+(11*8)(r31)
+	lfd	fp12,_UC_FREGS+(12*8)(r31)
+	lfd	fp13,_UC_FREGS+(13*8)(r31)
+	lfd	fp14,_UC_FREGS+(14*8)(r31)
+	lfd	fp15,_UC_FREGS+(15*8)(r31)
+	lfd	fp16,_UC_FREGS+(16*8)(r31)
+	lfd	fp17,_UC_FREGS+(17*8)(r31)
+	lfd	fp18,_UC_FREGS+(18*8)(r31)
+	lfd	fp19,_UC_FREGS+(19*8)(r31)
+	lfd	fp20,_UC_FREGS+(20*8)(r31)
+	lfd	fp21,_UC_FREGS+(21*8)(r31)
+	lfd	fp22,_UC_FREGS+(22*8)(r31)
+	lfd	fp23,_UC_FREGS+(23*8)(r31)
+	lfd	fp24,_UC_FREGS+(24*8)(r31)
+	lfd	fp25,_UC_FREGS+(25*8)(r31)
+	lfd	fp26,_UC_FREGS+(26*8)(r31)
+	lfd	fp27,_UC_FREGS+(27*8)(r31)
+	lfd	fp28,_UC_FREGS+(28*8)(r31)
+	lfd	fp29,_UC_FREGS+(29*8)(r31)
+	lfd	fp30,_UC_FREGS+(30*8)(r31)
+	lfd	fp31,_UC_FREGS+(31*8)(r31)
+
+	/* Restore LR and CCR, and set CTR to the NIP value */
+	lwz	r3,_UC_GREGS+(PT_LNK*4)(r31)
+	lwz	r4,_UC_GREGS+(PT_NIP*4)(r31)
+	lwz	r5,_UC_GREGS+(PT_CCR*4)(r31)
+	mtlr	r3
+	mtctr	r4
+	mtcr	r5
+
+	/* Restore the general registers */
+	lwz	r1,_UC_GREGS+(PT_R1*4)(r31)
+	lwz	r3,_UC_GREGS+(PT_R3*4)(r31)
+	lwz	r4,_UC_GREGS+(PT_R4*4)(r31)
+	lwz	r5,_UC_GREGS+(PT_R5*4)(r31)
+	lwz	r6,_UC_GREGS+(PT_R6*4)(r31)
+	lwz	r7,_UC_GREGS+(PT_R7*4)(r31)
+	lwz	r8,_UC_GREGS+(PT_R8*4)(r31)
+	lwz	r9,_UC_GREGS+(PT_R9*4)(r31)
+	lwz	r10,_UC_GREGS+(PT_R10*4)(r31)
+	lwz	r11,_UC_GREGS+(PT_R11*4)(r31)
+	lwz	r12,_UC_GREGS+(PT_R12*4)(r31)
+	lwz	r13,_UC_GREGS+(PT_R13*4)(r31)
+	lwz	r14,_UC_GREGS+(PT_R14*4)(r31)
+	lwz	r15,_UC_GREGS+(PT_R15*4)(r31)
+	lwz	r16,_UC_GREGS+(PT_R16*4)(r31)
+	lwz	r17,_UC_GREGS+(PT_R17*4)(r31)
+	lwz	r18,_UC_GREGS+(PT_R18*4)(r31)
+	lwz	r19,_UC_GREGS+(PT_R19*4)(r31)
+	lwz	r20,_UC_GREGS+(PT_R20*4)(r31)
+	lwz	r21,_UC_GREGS+(PT_R21*4)(r31)
+	lwz	r22,_UC_GREGS+(PT_R22*4)(r31)
+	lwz	r23,_UC_GREGS+(PT_R23*4)(r31)
+	lwz	r24,_UC_GREGS+(PT_R24*4)(r31)
+	lwz	r25,_UC_GREGS+(PT_R25*4)(r31)
+	lwz	r26,_UC_GREGS+(PT_R26*4)(r31)
+	lwz	r27,_UC_GREGS+(PT_R27*4)(r31)
+	lwz	r28,_UC_GREGS+(PT_R28*4)(r31)
+	lwz	r29,_UC_GREGS+(PT_R29*4)(r31)
+	lwz	r30,_UC_GREGS+(PT_R30*4)(r31)
+	lwz	r31,_UC_GREGS+(PT_R31*4)(r31)
+
+	bctr
+
+L(error_exit):
+	lwz	r31,12(r1)
+	lwz	r0,20(r1)
+	addi	r1,r1,16
+	mtlr	r0
+	blr
+	
+L(do_sigret):
+	addi	r1,r3,-0xd0
+	li	r0,SYS_ify(rt_sigreturn)
+	sc
+	/* NOTREACHED */
+
+PSEUDO_END(__setcontext)
+
+weak_alias(__setcontext, setcontext)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext.S
new file mode 100644
index 0000000000..88cf0dae8f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext.S
@@ -0,0 +1,233 @@
+/* Save current context and jump to a new context.
+   Copyright (C) 2002 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
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+
+#define __ASSEMBLY__
+#include <asm/ptrace.h>
+#include "ucontext_i.h"
+
+ENTRY(__swapcontext)
+	/* Save the current context */
+	stw	r0,_UC_GREGS+(PT_R0*4)(r3)
+	stw	r1,_UC_GREGS+(PT_R1*4)(r3)
+	mflr	r0
+	stwu	r1,-16(r1)
+	stw	r0,20(r1)
+	stw	r31,12(r1)
+	stw	r31,_UC_GREGS+(PT_R31*4)(r3)
+	mr	r31,r4			/* new context pointer */
+	stw	r0,_UC_GREGS+(PT_LNK*4)(r3)
+	stw	r0,_UC_GREGS+(PT_NIP*4)(r3)
+	stw	r2,_UC_GREGS+(PT_R2*4)(r3)
+	stw	r4,_UC_GREGS+(PT_R4*4)(r3)
+	stw	r5,_UC_GREGS+(PT_R5*4)(r3)
+	stw	r6,_UC_GREGS+(PT_R6*4)(r3)
+	stw	r7,_UC_GREGS+(PT_R7*4)(r3)
+	stw	r8,_UC_GREGS+(PT_R8*4)(r3)
+	stw	r9,_UC_GREGS+(PT_R9*4)(r3)
+	stw	r10,_UC_GREGS+(PT_R10*4)(r3)
+	stw	r11,_UC_GREGS+(PT_R11*4)(r3)
+	stw	r12,_UC_GREGS+(PT_R12*4)(r3)
+	stw	r13,_UC_GREGS+(PT_R13*4)(r3)
+	stw	r14,_UC_GREGS+(PT_R14*4)(r3)
+	stw	r15,_UC_GREGS+(PT_R15*4)(r3)
+	stw	r16,_UC_GREGS+(PT_R16*4)(r3)
+	stw	r17,_UC_GREGS+(PT_R17*4)(r3)
+	stw	r18,_UC_GREGS+(PT_R18*4)(r3)
+	stw	r19,_UC_GREGS+(PT_R19*4)(r3)
+	stw	r20,_UC_GREGS+(PT_R20*4)(r3)
+	stw	r21,_UC_GREGS+(PT_R21*4)(r3)
+	stw	r22,_UC_GREGS+(PT_R22*4)(r3)
+	stw	r23,_UC_GREGS+(PT_R23*4)(r3)
+	stw	r24,_UC_GREGS+(PT_R24*4)(r3)
+	stw	r25,_UC_GREGS+(PT_R25*4)(r3)
+	stw	r26,_UC_GREGS+(PT_R26*4)(r3)
+	stw	r27,_UC_GREGS+(PT_R27*4)(r3)
+	stw	r28,_UC_GREGS+(PT_R28*4)(r3)
+	stw	r29,_UC_GREGS+(PT_R29*4)(r3)
+	stw	r30,_UC_GREGS+(PT_R30*4)(r3)
+	mfctr	r0
+	stw	r0,_UC_GREGS+(PT_CTR*4)(r3)
+	mfxer	r0
+	stw	r0,_UC_GREGS+(PT_XER*4)(r3)
+	mfcr	r0
+	stw	r0,_UC_GREGS+(PT_CCR*4)(r3)
+
+	/* Set the return value of swapcontext to "success".  R3 is the only 
+	   register whose value is not preserved in the saved context.  */
+	li	r0,0
+	stw	r0,_UC_GREGS+(PT_R3*4)(r3)
+
+	/* Zero fill fields that can't be set in user state. */
+	stw	r0,_UC_GREGS+(PT_MSR*4)(r3)
+	stw	r0,_UC_GREGS+(PT_MQ*4)(r3)
+
+	/* Save the floating-point registers */
+	stfd	fp0,_UC_FREGS+(0*8)(r3)
+	stfd	fp1,_UC_FREGS+(1*8)(r3)
+	stfd	fp2,_UC_FREGS+(2*8)(r3)
+	stfd	fp3,_UC_FREGS+(3*8)(r3)
+	stfd	fp4,_UC_FREGS+(4*8)(r3)
+	stfd	fp5,_UC_FREGS+(5*8)(r3)
+	stfd	fp6,_UC_FREGS+(6*8)(r3)
+	stfd	fp7,_UC_FREGS+(7*8)(r3)
+	stfd	fp8,_UC_FREGS+(8*8)(r3)
+	stfd	fp9,_UC_FREGS+(9*8)(r3)
+	stfd	fp10,_UC_FREGS+(10*8)(r3)
+	stfd	fp11,_UC_FREGS+(11*8)(r3)
+	stfd	fp12,_UC_FREGS+(12*8)(r3)
+	stfd	fp13,_UC_FREGS+(13*8)(r3)
+	stfd	fp14,_UC_FREGS+(14*8)(r3)
+	stfd	fp15,_UC_FREGS+(15*8)(r3)
+	stfd	fp16,_UC_FREGS+(16*8)(r3)
+	stfd	fp17,_UC_FREGS+(17*8)(r3)
+	stfd	fp18,_UC_FREGS+(18*8)(r3)
+	stfd	fp19,_UC_FREGS+(19*8)(r3)
+	stfd	fp20,_UC_FREGS+(20*8)(r3)
+	stfd	fp21,_UC_FREGS+(21*8)(r3)
+	stfd	fp22,_UC_FREGS+(22*8)(r3)
+	stfd	fp23,_UC_FREGS+(23*8)(r3)
+	stfd	fp24,_UC_FREGS+(24*8)(r3)
+	stfd	fp25,_UC_FREGS+(25*8)(r3)
+	stfd	fp26,_UC_FREGS+(26*8)(r3)
+	stfd	fp27,_UC_FREGS+(27*8)(r3)
+	stfd	fp28,_UC_FREGS+(28*8)(r3)
+	stfd	fp29,_UC_FREGS+(29*8)(r3)
+	mffs	fp0
+	stfd	fp30,_UC_FREGS+(30*8)(r3)
+	stfd	fp31,_UC_FREGS+(31*8)(r3)
+	stfd	fp0,_UC_FREGS+(32*8)(r3)
+
+	addi	r5,r3,_UC_SIGMASK
+	addi	r4,r4,_UC_SIGMASK
+	li	r3,SIG_SETMASK
+	bl	JUMPTARGET(sigprocmask)
+	cmpwi	r3,0
+	bne	L(error_exit)
+
+	/*
+	 * If the new ucontext refers to the point where we were interrupted
+	 * by a signal, we have to use the rt_sigreturn system call to
+	 * return to the context so we get both LR and CTR restored.
+	 *
+	 * Otherwise, the context we are restoring is either just after
+	 * a procedure call (getcontext/swapcontext) or at the beginning
+	 * of a procedure call (makecontext), so we don't need to restore
+	 * r0, xer, ctr.  We don't restore r2 since it will be used as
+	 * the TLS pointer.
+	 */
+	lwz	r0,_UC_GREGS+(PT_MSR*4)(r31)
+	cmpwi	r0,0
+	bne	L(do_sigret)
+
+	/* Restore the floating-point registers */
+	lfd	fp31,_UC_FREGS+(32*8)(r31)
+	lfd	fp0,_UC_FREGS+(0*8)(r31)
+	mtfsf	0xff,fp31
+	lfd	fp1,_UC_FREGS+(1*8)(r31)
+	lfd	fp2,_UC_FREGS+(2*8)(r31)
+	lfd	fp3,_UC_FREGS+(3*8)(r31)
+	lfd	fp4,_UC_FREGS+(4*8)(r31)
+	lfd	fp5,_UC_FREGS+(5*8)(r31)
+	lfd	fp6,_UC_FREGS+(6*8)(r31)
+	lfd	fp7,_UC_FREGS+(7*8)(r31)
+	lfd	fp8,_UC_FREGS+(8*8)(r31)
+	lfd	fp9,_UC_FREGS+(9*8)(r31)
+	lfd	fp10,_UC_FREGS+(10*8)(r31)
+	lfd	fp11,_UC_FREGS+(11*8)(r31)
+	lfd	fp12,_UC_FREGS+(12*8)(r31)
+	lfd	fp13,_UC_FREGS+(13*8)(r31)
+	lfd	fp14,_UC_FREGS+(14*8)(r31)
+	lfd	fp15,_UC_FREGS+(15*8)(r31)
+	lfd	fp16,_UC_FREGS+(16*8)(r31)
+	lfd	fp17,_UC_FREGS+(17*8)(r31)
+	lfd	fp18,_UC_FREGS+(18*8)(r31)
+	lfd	fp19,_UC_FREGS+(19*8)(r31)
+	lfd	fp20,_UC_FREGS+(20*8)(r31)
+	lfd	fp21,_UC_FREGS+(21*8)(r31)
+	lfd	fp22,_UC_FREGS+(22*8)(r31)
+	lfd	fp23,_UC_FREGS+(23*8)(r31)
+	lfd	fp24,_UC_FREGS+(24*8)(r31)
+	lfd	fp25,_UC_FREGS+(25*8)(r31)
+	lfd	fp26,_UC_FREGS+(26*8)(r31)
+	lfd	fp27,_UC_FREGS+(27*8)(r31)
+	lfd	fp28,_UC_FREGS+(28*8)(r31)
+	lfd	fp29,_UC_FREGS+(29*8)(r31)
+	lfd	fp30,_UC_FREGS+(30*8)(r31)
+	lfd	fp31,_UC_FREGS+(31*8)(r31)
+
+	/* Restore LR and CCR, and set CTR to the NIP value */
+	lwz	r3,_UC_GREGS+(PT_LNK*4)(r31)
+	lwz	r4,_UC_GREGS+(PT_NIP*4)(r31)
+	lwz	r5,_UC_GREGS+(PT_CCR*4)(r31)
+	mtlr	r3
+	mtctr	r4
+	mtcr	r5
+
+	/* Restore the general registers */
+	lwz	r1,_UC_GREGS+(PT_R1*4)(r31)
+	lwz	r3,_UC_GREGS+(PT_R3*4)(r31)
+	lwz	r4,_UC_GREGS+(PT_R4*4)(r31)
+	lwz	r5,_UC_GREGS+(PT_R5*4)(r31)
+	lwz	r6,_UC_GREGS+(PT_R6*4)(r31)
+	lwz	r7,_UC_GREGS+(PT_R7*4)(r31)
+	lwz	r8,_UC_GREGS+(PT_R8*4)(r31)
+	lwz	r9,_UC_GREGS+(PT_R9*4)(r31)
+	lwz	r10,_UC_GREGS+(PT_R10*4)(r31)
+	lwz	r11,_UC_GREGS+(PT_R11*4)(r31)
+	lwz	r12,_UC_GREGS+(PT_R12*4)(r31)
+	lwz	r13,_UC_GREGS+(PT_R13*4)(r31)
+	lwz	r14,_UC_GREGS+(PT_R14*4)(r31)
+	lwz	r15,_UC_GREGS+(PT_R15*4)(r31)
+	lwz	r16,_UC_GREGS+(PT_R16*4)(r31)
+	lwz	r17,_UC_GREGS+(PT_R17*4)(r31)
+	lwz	r18,_UC_GREGS+(PT_R18*4)(r31)
+	lwz	r19,_UC_GREGS+(PT_R19*4)(r31)
+	lwz	r20,_UC_GREGS+(PT_R20*4)(r31)
+	lwz	r21,_UC_GREGS+(PT_R21*4)(r31)
+	lwz	r22,_UC_GREGS+(PT_R22*4)(r31)
+	lwz	r23,_UC_GREGS+(PT_R23*4)(r31)
+	lwz	r24,_UC_GREGS+(PT_R24*4)(r31)
+	lwz	r25,_UC_GREGS+(PT_R25*4)(r31)
+	lwz	r26,_UC_GREGS+(PT_R26*4)(r31)
+	lwz	r27,_UC_GREGS+(PT_R27*4)(r31)
+	lwz	r28,_UC_GREGS+(PT_R28*4)(r31)
+	lwz	r29,_UC_GREGS+(PT_R29*4)(r31)
+	lwz	r30,_UC_GREGS+(PT_R30*4)(r31)
+	lwz	r31,_UC_GREGS+(PT_R31*4)(r31)
+
+	bctr
+
+L(error_exit):
+	lwz	r31,12(r1)
+	lwz	r0,20(r1)
+	addi	r1,r1,16
+	mtlr	r0
+	blr
+
+L(do_sigret):
+	addi	r1,r31,-0xd0
+	li	r0,SYS_ify(rt_sigreturn)
+	sc
+	/* NOTREACHED */
+
+PSEUDO_END(__swapcontext)
+
+weak_alias(__swapcontext, swapcontext)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/ucontext_i.h b/sysdeps/unix/sysv/linux/powerpc/powerpc32/ucontext_i.h
new file mode 100644
index 0000000000..e88a025d6a
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/ucontext_i.h
@@ -0,0 +1,30 @@
+/* Offsets and other constants needed in the *context() function
+   implementation.
+   Copyright (C) 2002 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
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#define SIG_BLOCK	0
+#define SIG_SETMASK	2
+
+#define _UC_LINK	4
+#define _UC_STACK_SP	8
+#define _UC_STACK_SIZE	16
+#define _UC_SIGMASK	64
+#define _UC_GREGS	192
+#define _UC_FREGS	384
+#define _UC_VREGS	656
diff --git a/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h b/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
index 0f7b19c70c..9ce93c8197 100644
--- a/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
@@ -26,9 +26,47 @@
    included in <signal.h>.  */
 #include <bits/sigcontext.h>
 
-/* A machine context is exactly a sigcontext.  */
+#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 vscr;
+	unsigned int vrsave;
+	unsigned int _pad[2];
+} 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, a machine context is exactly a sigcontext.  */
 typedef struct sigcontext mcontext_t;
 
+#endif
+
 /* Userlevel context.  */
 typedef struct ucontext
   {
@@ -36,12 +74,14 @@ typedef struct ucontext
     struct ucontext *uc_link;
     stack_t uc_stack;
 #if __WORDSIZE == 32
-    mcontext_t uc_mcontext;
-    __sigset_t uc_sigmask;
-#else
+    /* These fields are for backwards compatibility. */
+    int uc_pad[7];
+    mcontext_t *uc_regs;
+    unsigned int uc_oldsigmask[2];
+    int uc_pad2;
+#endif
     sigset_t    uc_sigmask;
     mcontext_t  uc_mcontext;  /* last for extensibility */
-#endif
   } ucontext_t;
 
 #endif /* sys/ucontext.h */