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[PATCH 2/2] ARM uprobes support


Basic uprobes support for ARM.

Signed-off-by: Wade Farnsworth <wade_farnsworth@mentor.com>
---
 runtime/uprobes2/uprobes_arch.c |    2 +
 runtime/uprobes2/uprobes_arch.h |    2 +
 runtime/uprobes2/uprobes_arm.c  | 1914 +++++++++++++++++++++++++++++++++++++++
 runtime/uprobes2/uprobes_arm.h  |  114 +++
 4 files changed, 2032 insertions(+), 0 deletions(-)
 create mode 100644 runtime/uprobes2/uprobes_arm.c
 create mode 100644 runtime/uprobes2/uprobes_arm.h

diff --git a/runtime/uprobes2/uprobes_arch.c b/runtime/uprobes2/uprobes_arch.c
index a91d5b6..1df4fdd 100644
--- a/runtime/uprobes2/uprobes_arch.c
+++ b/runtime/uprobes2/uprobes_arch.c
@@ -1,5 +1,7 @@
 #if defined (__x86_64__) || defined(__i386)
 #include "uprobes_x86.c"
+#elif defined (__arm__)
+#include "uprobes_arm.c"
 #elif defined (__powerpc__)
 #include "../uprobes/uprobes_ppc.c"
 #elif defined (__s390__) || defined (__s390x__)
diff --git a/runtime/uprobes2/uprobes_arch.h b/runtime/uprobes2/uprobes_arch.h
index cce5775..a499279 100644
--- a/runtime/uprobes2/uprobes_arch.h
+++ b/runtime/uprobes2/uprobes_arch.h
@@ -1,5 +1,7 @@
 #if defined (__x86_64__) || defined(__i386)
 #include "uprobes_x86.h"
+#elif defined (__arm__)
+#include "uprobes_arm.h"
 #elif defined (__powerpc__)
 #include "../uprobes/uprobes_ppc.h"
 #elif defined (__s390__) || defined (__s390x__)
diff --git a/runtime/uprobes2/uprobes_arm.c b/runtime/uprobes2/uprobes_arm.c
new file mode 100644
index 0000000..37e9a6f
--- /dev/null
+++ b/runtime/uprobes2/uprobes_arm.c
@@ -0,0 +1,1914 @@
+/*
+ *  Userspace Probes (UProbes)
+ *  uprobes.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright (C) 2011 Mentor Graphics Corporation
+ *
+ * Instruction validation and emulation code is based on
+ * ARM kprobes which is
+ * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
+ * Copyright (C) 2006, 2007 Motorola Inc.
+ */
+/*
+ * In versions of uprobes built in the SystemTap runtime, this file
+ * is #included at the end of uprobes.c.
+ */
+
+/*
+ * We do not have hardware single-stepping on ARM, This
+ * effort is further complicated by the ARM not having a
+ * "next PC" register.  Instructions that change the PC
+ * can't be safely single-stepped in a MP environment, so
+ * we have a lot of work to do:
+ *
+ * In the prepare phase:
+ *   *) If it is an instruction that does anything
+ *      with the CPU mode, we reject it for a uprobe.
+ *      (This is out of laziness rather than need.  The
+ *      instructions could be simulated.)
+ *
+ *   *) Otherwise, decode the instruction rewriting its
+ *      registers to take fixed, ordered registers and
+ *      setting a handler for it to run the instruction.
+ *
+ * In the execution phase by an instruction's handler:
+ *
+ *   *) If the PC is written to by the instruction, the
+ *      instruction must be fully simulated in software.
+ *
+ *   *) Otherwise, a modified form of the instruction is
+ *      directly executed.  Its handler calls the
+ *      instruction in insn[0].  In insn[1] is a
+ *      "mov pc, lr" to return.
+ *
+ *      Before calling, load up the reordered registers
+ *      from the original instruction's registers.  If one
+ *      of the original input registers is the PC, compute
+ *      and adjust the appropriate input register.
+ *
+ *	After call completes, copy the output registers to
+ *      the original instruction's original registers.
+ *
+ * We don't use a real breakpoint instruction since that
+ * would have us in the kernel go from SVC mode to SVC
+ * mode losing the link register.  Instead we use an
+ * undefined instruction.  To simplify processing, the
+ * undefined instruction used for uprobes must be reserved
+ * exclusively for uprobes use.
+ *
+ * TODO: ifdef out some instruction decoding based on architecture.
+ */
+
+#define APSR_MASK       0xf80f0000      /* N, Z, C, V, Q and GE flags */
+
+#if __LINUX_ARM_ARCH__ >= 7
+
+/* str_pc_offset is architecturally defined from ARMv7 onwards */
+#define str_pc_offset 8
+#define find_str_pc_offset()
+
+#else /* __LINUX_ARM_ARCH__ < 7 */
+
+/* We need a run-time check to determine str_pc_offset */
+extern int str_pc_offset;
+void find_str_pc_offset(void);
+
+#endif
+
+static inline void bx_write_pc(long pcv, struct pt_regs *regs)
+{
+	long cpsr = regs->ARM_cpsr;
+	if (pcv & 0x1) {
+		cpsr |= PSR_T_BIT;
+		pcv &= ~0x1;
+	} else {
+		cpsr &= ~PSR_T_BIT;
+		pcv &= ~0x2;    /* Avoid UNPREDICTABLE address allignment */
+	}
+	regs->ARM_cpsr = cpsr;
+	regs->ARM_pc = pcv;
+}
+
+#if __LINUX_ARM_ARCH__ >= 6
+
+/* Kernels built for >= ARMv6 should never run on <= ARMv5 hardware, so... */
+#define load_write_pc_interworks true
+#define test_load_write_pc_interworking()
+
+#else /* __LINUX_ARM_ARCH__ < 6 */
+
+/* We need run-time testing to determine if load_write_pc() should interwork.
+ * */
+extern bool load_write_pc_interworks;
+void test_load_write_pc_interworking(void);
+
+#endif
+
+static inline void load_write_pc(long pcv, struct pt_regs *regs)
+{
+	if (load_write_pc_interworks)
+		bx_write_pc(pcv, regs);
+	else
+		regs->ARM_pc = pcv;
+}
+
+#if __LINUX_ARM_ARCH__ >= 7
+
+#define alu_write_pc_interworks true
+#define test_alu_write_pc_interworking()
+
+#elif __LINUX_ARM_ARCH__ <= 5
+
+/* Kernels built for <= ARMv5 should never run on >= ARMv6 hardware, so... */
+#define alu_write_pc_interworks false
+#define test_alu_write_pc_interworking()
+
+#else /* __LINUX_ARM_ARCH__ == 6 */
+
+/* We could be an ARMv6 binary on ARMv7 hardware so we need a run-time check.
+ * */
+extern bool alu_write_pc_interworks;
+void test_alu_write_pc_interworking(void);
+
+#endif /* __LINUX_ARM_ARCH__ == 6 */
+
+static inline void alu_write_pc(long pcv, struct pt_regs *regs)
+{
+	if (alu_write_pc_interworks)
+		bx_write_pc(pcv, regs);
+	else
+		regs->ARM_pc = pcv;
+}
+
+enum uprobe_insn {
+	INSN_REJECTED,
+	INSN_GOOD,
+	INSN_GOOD_NO_SLOT
+};
+
+typedef enum uprobe_insn (uprobe_decode_insn_t)(uprobe_opcode_t,
+		struct uprobe_probept_arch_info *);
+
+/*
+ * Test if load/store instructions writeback the address register.
+ * if P (bit 24) == 0 or W (bit 21) == 1
+ */
+#define is_writeback(insn) ((insn ^ 0x01000000) & 0x01200000)
+
+/*
+ * The following definitions and macros are used to build instruction
+ * decoding tables for use by uprobe_decode_insn.
+ *
+ * These tables are a concatenation of entries each of which consist of one of
+ * the decode_* structs. All of the fields in every type of decode structure
+ * are of the union type decode_item, therefore the entire decode table can be
+ * viewed as an array of these and declared like:
+ *
+ *	static const union decode_item table_name[] = {};
+ *
+ * In order to construct each entry in the table, macros are used to
+ * initialise a number of sequential decode_item values in a layout which
+ * matches the relevant struct. E.g. DECODE_SIMULATE initialise a struct
+ * decode_simulate by initialising four decode_item objects like this...
+ *
+ *	{.bits = _type},
+ *	{.bits = _mask},
+ *	{.bits = _value},
+ *	{.handler = _handler},
+ *
+ * Initialising a specified member of the union means that the compiler
+ * will produce a warning if the argument is of an incorrect type.
+ *
+ * Below is a list of each of the macros used to initialise entries and a
+ * description of the action performed when that entry is matched to an
+ * instruction. A match is found when (instruction & mask) == value.
+ *
+ * DECODE_TABLE(mask, value, table)
+ *	Instruction decoding jumps to parsing the new sub-table 'table'.
+ *
+ * DECODE_CUSTOM(mask, value, decoder)
+ *	The custom function 'decoder' is called to the complete decoding
+ *	of an instruction.
+ *
+ * DECODE_SIMULATE(mask, value, handler)
+ *	Set the probes instruction handler to 'handler', this will be used
+ *	to simulate the instruction when the probe is hit. Decoding returns
+ *	with INSN_GOOD_NO_SLOT.
+ *
+ * DECODE_EMULATE(mask, value, handler)
+ *	Set the probes instruction handler to 'handler', this will be used
+ *	to emulate the instruction when the probe is hit. The modified
+ *	instruction (see below) is placed in the probes instruction slot so it
+ *	may be called by the emulation code. Decoding returns with INSN_GOOD.
+ *
+ * DECODE_REJECT(mask, value)
+ *	Instruction decoding fails with INSN_REJECTED
+ *
+ * DECODE_OR(mask, value)
+ *	This allows the mask/value test of multiple table entries to be
+ *	logically ORed. Once an 'or' entry is matched the decoding action to
+ *	be performed is that of the next entry which isn't an 'or'. E.g.
+ *
+ *		DECODE_OR	(mask1, value1)
+ *		DECODE_OR	(mask2, value2)
+ *		DECODE_SIMULATE	(mask3, value3, simulation_handler)
+ *
+ *	This means that if any of the three mask/value pairs match the
+ *	instruction being decoded, then 'simulation_handler' will be used
+ *	for it.
+ *
+ * Both the SIMULATE and EMULATE macros have a second form which take an
+ * additional 'regs' argument.
+ *
+ *	DECODE_SIMULATEX(mask, value, handler, regs)
+ *	DECODE_EMULATEX	(mask, value, handler, regs)
+ *
+ * These are used to specify what kind of CPU register is encoded in each of the
+ * least significant 5 nibbles of the instruction being decoded. The regs value
+ * is specified using the REGS macro, this takes any of the REG_TYPE_* values
+ * from enum decode_reg_type as arguments; only the '*' part of the name is
+ * given. E.g.
+ *
+ *	REGS(0, ANY, NOPC, 0, ANY)
+ *
+ * This indicates an instruction is encoded like:
+ *
+ *	bits 19..16	ignore
+ *	bits 15..12	any register allowed here
+ *	bits 11.. 8	any register except PC allowed here
+ *	bits  7.. 4	ignore
+ *	bits  3.. 0	any register allowed here
+ *
+ * This register specification is checked after a decode table entry is found to
+ * match an instruction (through the mask/value test). Any invalid register then
+ * found in the instruction will cause decoding to fail with INSN_REJECTED. In
+ * the above example this would happen if bits 11..8 of the instruction were
+ * 1111, indicating R15 or PC.
+ *
+ * As well as checking for legal combinations of registers, this data is also
+ * used to modify the registers encoded in the instructions so that an
+ * emulation routines can use it. (See decode_regs() and INSN_NEW_BITS.)
+ *
+ * Here is a real example which matches ARM instructions of the form
+ * "AND <Rd>,<Rn>,<Rm>,<shift> <Rs>"
+ *
+ *	DECODE_EMULATEX	(0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
+ *						 REGS(ANY, ANY, NOPC, 0, ANY)),
+ *						      ^    ^    ^        ^
+ *						      Rn   Rd   Rs       Rm
+ *
+ * Decoding the instruction "AND R4, R5, R6, ASL R15" will be rejected because
+ * Rs == R15
+ *
+ * Decoding the instruction "AND R4, R5, R6, ASL R7" will be accepted and the
+ * instruction will be modified to "AND R0, R2, R3, ASL R1" and then placed into
+ * the uprobes instruction slot. This can then be called later by the handler
+ * function emulate_rd12rn16rm0rs8_rwflags in order to simulate the instruction.
+ */
+
+enum decode_type {
+	DECODE_TYPE_END,
+	DECODE_TYPE_TABLE,
+	DECODE_TYPE_CUSTOM,
+	DECODE_TYPE_SIMULATE,
+	DECODE_TYPE_EMULATE,
+	DECODE_TYPE_OR,
+	DECODE_TYPE_REJECT,
+	NUM_DECODE_TYPES /* Must be last enum */
+};
+
+#define DECODE_TYPE_BITS	4
+#define DECODE_TYPE_MASK	((1 << DECODE_TYPE_BITS) - 1)
+
+enum decode_reg_type {
+	REG_TYPE_NONE = 0, /* Not a register, ignore */
+	REG_TYPE_ANY,	   /* Any register allowed */
+	REG_TYPE_SAMEAS16, /* Register should be same as that at bits 19..16 */
+	REG_TYPE_SP,	   /* Register must be SP */
+	REG_TYPE_PC,	   /* Register must be PC */
+	REG_TYPE_NOSP,	   /* Register must not be SP */
+	REG_TYPE_NOSPPC,   /* Register must not be SP or PC */
+	REG_TYPE_NOPC,	   /* Register must not be PC */
+	REG_TYPE_NOPCWB,   /* No PC if load/store write-back flag also set */
+
+	/* The following types are used when the encoding for PC indicates
+	 * another instruction form. This distiction only matters for test
+	 * case coverage checks.
+	 */
+	REG_TYPE_NOPCX,	   /* Register must not be PC */
+	REG_TYPE_NOSPPCX,  /* Register must not be SP or PC */
+
+	/* Alias to allow '0' arg to be used in REGS macro. */
+	REG_TYPE_0 = REG_TYPE_NONE
+};
+
+#define REGS(r16, r12, r8, r4, r0)	\
+	((REG_TYPE_##r16) << 16) +	\
+	((REG_TYPE_##r12) << 12) +	\
+	((REG_TYPE_##r8) << 8) +	\
+	((REG_TYPE_##r4) << 4) +	\
+	(REG_TYPE_##r0)
+
+union decode_item {
+	u32			bits;
+	const union decode_item	*table;
+	uprobe_insn_handler_t	*handler;
+	uprobe_decode_insn_t	*decoder;
+};
+
+
+#define DECODE_END			\
+	{.bits = DECODE_TYPE_END}
+
+
+struct decode_header {
+	union decode_item	type_regs;
+	union decode_item	mask;
+	union decode_item	value;
+};
+
+#define DECODE_HEADER(_type, _mask, _value, _regs)		\
+	{.bits = (_type) | ((_regs) << DECODE_TYPE_BITS)},	\
+	{.bits = (_mask)},					\
+	{.bits = (_value)}
+
+
+struct decode_table {
+	struct decode_header	header;
+	union decode_item	table;
+};
+
+#define DECODE_TABLE(_mask, _value, _table)			\
+	DECODE_HEADER(DECODE_TYPE_TABLE, _mask, _value, 0),	\
+	{.table = (_table)}
+
+
+struct decode_custom {
+	struct decode_header	header;
+	union decode_item	decoder;
+};
+
+#define DECODE_CUSTOM(_mask, _value, _decoder)			\
+	DECODE_HEADER(DECODE_TYPE_CUSTOM, _mask, _value, 0),	\
+	{.decoder = (_decoder)}
+
+
+struct decode_simulate {
+	struct decode_header	header;
+	union decode_item	handler;
+};
+
+#define DECODE_SIMULATEX(_mask, _value, _handler, _regs)		\
+	DECODE_HEADER(DECODE_TYPE_SIMULATE, _mask, _value, _regs),	\
+	{.handler = (_handler)}
+
+#define DECODE_SIMULATE(_mask, _value, _handler)	\
+	DECODE_SIMULATEX(_mask, _value, _handler, 0)
+
+
+struct decode_emulate {
+	struct decode_header	header;
+	union decode_item	handler;
+};
+
+#define DECODE_EMULATEX(_mask, _value, _handler, _regs)			\
+	DECODE_HEADER(DECODE_TYPE_EMULATE, _mask, _value, _regs),	\
+	{.handler = (_handler)}
+
+#define DECODE_EMULATE(_mask, _value, _handler)		\
+	DECODE_EMULATEX(_mask, _value, _handler, 0)
+
+
+struct decode_or {
+	struct decode_header	header;
+};
+
+#define DECODE_OR(_mask, _value)				\
+	DECODE_HEADER(DECODE_TYPE_OR, _mask, _value, 0)
+
+
+struct decode_reject {
+	struct decode_header	header;
+};
+
+#define DECODE_REJECT(_mask, _value)				\
+	DECODE_HEADER(DECODE_TYPE_REJECT, _mask, _value, 0)
+
+#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
+
+#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
+
+#if  __LINUX_ARM_ARCH__ >= 6
+#define BLX(reg)	"blx	"reg"		\n\t"
+#else
+#define BLX(reg)	"mov	lr, pc		\n\t"	\
+			"mov	pc, "reg"	\n\t"
+#endif
+
+#ifndef find_str_pc_offset
+
+/*
+ * For STR and STM instructions, an ARM core may choose to use either
+ * a +8 or a +12 displacement from the current instruction's address.
+ * Whichever value is chosen for a given core, it must be the same for
+ * both instructions and may not change.  This function measures it.
+ */
+
+int str_pc_offset;
+
+void find_str_pc_offset(void)
+{
+	int addr, scratch, ret;
+
+	__asm__ (
+		"sub	%[ret], pc, #4		\n\t"
+		"str	pc, %[addr]		\n\t"
+		"ldr	%[scr], %[addr]		\n\t"
+		"sub	%[ret], %[scr], %[ret]	\n\t"
+		: [ret] "=r" (ret), [scr] "=r" (scratch), [addr] "+m" (addr));
+
+	str_pc_offset = ret;
+}
+
+#endif /* !find_str_pc_offset */
+
+
+#ifndef test_load_write_pc_interworking
+
+bool load_write_pc_interworks;
+
+void test_load_write_pc_interworking(void)
+{
+	int arch = cpu_architecture();
+	BUG_ON(arch == CPU_ARCH_UNKNOWN);
+	load_write_pc_interworks = arch >= CPU_ARCH_ARMv5T;
+}
+
+#endif /* !test_load_write_pc_interworking */
+
+
+#ifndef test_alu_write_pc_interworking
+
+bool alu_write_pc_interworks;
+
+void test_alu_write_pc_interworking(void)
+{
+	int arch = cpu_architecture();
+	BUG_ON(arch == CPU_ARCH_UNKNOWN);
+	alu_write_pc_interworks = arch >= CPU_ARCH_ARMv7;
+}
+
+#endif /* !test_alu_write_pc_interworking */
+
+
+void arm_uprobe_decode_init(void)
+{
+	find_str_pc_offset();
+	test_load_write_pc_interworking();
+	test_alu_write_pc_interworking();
+}
+
+
+static unsigned long __check_eq(unsigned long cpsr)
+{
+	return cpsr & PSR_Z_BIT;
+}
+
+static unsigned long __check_ne(unsigned long cpsr)
+{
+	return (~cpsr) & PSR_Z_BIT;
+}
+
+static unsigned long __check_cs(unsigned long cpsr)
+{
+	return cpsr & PSR_C_BIT;
+}
+
+static unsigned long __check_cc(unsigned long cpsr)
+{
+	return (~cpsr) & PSR_C_BIT;
+}
+
+static unsigned long __check_mi(unsigned long cpsr)
+{
+	return cpsr & PSR_N_BIT;
+}
+
+static unsigned long __check_pl(unsigned long cpsr)
+{
+	return (~cpsr) & PSR_N_BIT;
+}
+
+static unsigned long __check_vs(unsigned long cpsr)
+{
+	return cpsr & PSR_V_BIT;
+}
+
+static unsigned long __check_vc(unsigned long cpsr)
+{
+	return (~cpsr) & PSR_V_BIT;
+}
+
+static unsigned long __check_hi(unsigned long cpsr)
+{
+	cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+	return cpsr & PSR_C_BIT;
+}
+
+static unsigned long __check_ls(unsigned long cpsr)
+{
+	cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+	return (~cpsr) & PSR_C_BIT;
+}
+
+static unsigned long __check_ge(unsigned long cpsr)
+{
+	cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+	return (~cpsr) & PSR_N_BIT;
+}
+
+static unsigned long __check_lt(unsigned long cpsr)
+{
+	cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+	return cpsr & PSR_N_BIT;
+}
+
+static unsigned long __check_gt(unsigned long cpsr)
+{
+	unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+	temp |= (cpsr << 1);			 /* PSR_N_BIT |= PSR_Z_BIT */
+	return (~temp) & PSR_N_BIT;
+}
+
+static unsigned long __check_le(unsigned long cpsr)
+{
+	unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+	temp |= (cpsr << 1);			 /* PSR_N_BIT |= PSR_Z_BIT */
+	return temp & PSR_N_BIT;
+}
+
+static unsigned long __check_al(unsigned long cpsr)
+{
+	return true;
+}
+
+uprobe_check_cc * const uprobe_condition_checks[16] = {
+	&__check_eq, &__check_ne, &__check_cs, &__check_cc,
+	&__check_mi, &__check_pl, &__check_vs, &__check_vc,
+	&__check_hi, &__check_ls, &__check_ge, &__check_lt,
+	&__check_gt, &__check_le, &__check_al, &__check_al
+};
+
+/*
+ * To avoid the complications of mimicing single-stepping on a
+ * processor without a Next-PC or a single-step mode, and to
+ * avoid having to deal with the side-effects of boosting, we
+ * simulate or emulate (almost) all ARM instructions.
+ *
+ * "Simulation" is where the instruction's behavior is duplicated in
+ * C code.  "Emulation" is where the original instruction is rewritten
+ * and executed, often by altering its registers.
+ *
+ * By having all behavior of the uprobe'd instruction completed before
+ * returning from the uprobe_handler(), all locks (scheduler and
+ * interrupt) can safely be released.  There is no need for secondary
+ * breakpoints, no race with MP or preemptable kernels, nor having to
+ * clean up resources counts at a later time impacting overall system
+ * performance.  By rewriting the instruction, only the minimum registers
+ * need to be loaded and saved back optimizing performance.
+ *
+ * Calling the insnslot_*_rwflags version of a function doesn't hurt
+ * anything even when the CPSR flags aren't updated by the
+ * instruction.  It's just a little slower in return for saving
+ * a little space by not having a duplicate function that doesn't
+ * update the flags.  (The same optimization can be said for
+ * instructions that do or don't perform register writeback)
+ * Also, instructions can either read the flags, only write the
+ * flags, or read and write the flags.  To save combinations
+ * rather than for sheer performance, flag functions just assume
+ * read and write of flags.
+ */
+
+void uprobe_simulate_nop(struct uprobe_probept *p, struct pt_regs *regs)
+{
+}
+
+void uprobe_emulate_none(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	p->arch_info.insn_fn();
+}
+
+static void simulate_ldm1stm1(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rn = (insn >> 16) & 0xf;
+	int lbit = insn & (1 << 20);
+	int wbit = insn & (1 << 21);
+	int ubit = insn & (1 << 23);
+	int pbit = insn & (1 << 24);
+	long *addr = (long *)regs->uregs[rn];
+	int reg_bit_vector;
+	int reg_count;
+
+	reg_count = 0;
+	reg_bit_vector = insn & 0xffff;
+	while (reg_bit_vector) {
+		reg_bit_vector &= (reg_bit_vector - 1);
+		++reg_count;
+	}
+
+	if (!ubit)
+		addr -= reg_count;
+	addr += (!pbit == !ubit);
+
+	reg_bit_vector = insn & 0xffff;
+	while (reg_bit_vector) {
+		int reg = __ffs(reg_bit_vector);
+		reg_bit_vector &= (reg_bit_vector - 1);
+		if (lbit)
+			regs->uregs[reg] = *addr++;
+		else
+			*addr++ = regs->uregs[reg];
+	}
+
+	if (wbit) {
+		if (!ubit)
+			addr -= reg_count;
+		addr -= (!pbit == !ubit);
+		regs->uregs[rn] = (long)addr;
+	}
+}
+
+static void simulate_stm1_pc(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	regs->ARM_pc = (long)p->vaddr + str_pc_offset;
+	simulate_ldm1stm1(p, regs);
+	regs->ARM_pc = (long)p->vaddr + 4;
+}
+
+static void simulate_ldm1_pc(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	simulate_ldm1stm1(p, regs);
+	load_write_pc(regs->ARM_pc, regs);
+}
+
+static void
+emulate_generic_r0_12_noflags(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	register void *rregs asm("r1") = regs;
+	register void *rfn asm("lr") = p->arch_info.insn_fn;
+
+	__asm__ __volatile__ (
+		"stmdb	sp!, {%[regs], r11}	\n\t"
+		"ldmia	%[regs], {r0-r12}	\n\t"
+#if __LINUX_ARM_ARCH__ >= 6
+		"blx	%[fn]			\n\t"
+#else
+		"str	%[fn], [sp, #-4]!	\n\t"
+		"adr	lr, 1f			\n\t"
+		"ldr	pc, [sp], #4		\n\t"
+		"1:				\n\t"
+#endif
+		"ldr	lr, [sp], #4		\n\t" /* lr = regs */
+		"stmia	lr, {r0-r12}		\n\t"
+		"ldr	r11, [sp], #4		\n\t"
+		: [regs] "=r" (rregs), [fn] "=r" (rfn)
+		: "0" (rregs), "1" (rfn)
+		: "r0", "r2", "r3", "r4", "r5", "r6", "r7",
+		  "r8", "r9", "r10", "r12", "memory", "cc"
+		);
+}
+
+static void
+emulate_generic_r2_14_noflags(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	emulate_generic_r0_12_noflags(p, (struct pt_regs *)(regs->uregs+2));
+}
+
+static void
+emulate_ldm_r3_15(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	emulate_generic_r0_12_noflags(p, (struct pt_regs *)(regs->uregs+3));
+	load_write_pc(regs->ARM_pc, regs);
+}
+
+enum uprobe_insn
+uprobe_decode_ldmstm(uprobe_opcode_t insn, struct uprobe_probept_arch_info *ai)
+{
+	uprobe_insn_handler_t *handler = 0;
+	unsigned reglist = insn & 0xffff;
+	int is_ldm = insn & 0x100000;
+	int rn = (insn >> 16) & 0xf;
+
+	if (rn <= 12 && (reglist & 0xe000) == 0) {
+		/* Instruction only uses registers in the range R0..R12 */
+		handler = emulate_generic_r0_12_noflags;
+
+	} else if (rn >= 2 && (reglist & 0x8003) == 0) {
+		/* Instruction only uses registers in the range R2..R14 */
+		rn -= 2;
+		reglist >>= 2;
+		handler = emulate_generic_r2_14_noflags;
+
+	} else if (rn >= 3 && (reglist & 0x0007) == 0) {
+		/* Instruction only uses registers in the range R3..R15 */
+		if (is_ldm && (reglist & 0x8000)) {
+			rn -= 3;
+			reglist >>= 3;
+			handler = emulate_ldm_r3_15;
+		}
+	}
+
+	if (handler) {
+		/* We can emulate the instruction in (possibly) modified form */
+		ai->insn[0] = (insn & 0xfff00000) | (rn << 16) | reglist;
+		ai->insn_handler = handler;
+		return INSN_GOOD;
+	}
+
+	/* Fallback to slower simulation... */
+	if (reglist & 0x8000)
+		handler = is_ldm ? simulate_ldm1_pc : simulate_stm1_pc;
+	else
+		handler = simulate_ldm1stm1;
+	ai->insn_handler = handler;
+	return INSN_GOOD_NO_SLOT;
+}
+
+static void simulate_bbl(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	long iaddr = (long)p->vaddr;
+	int disp  = branch_displacement(insn);
+
+	if (insn & (1 << 24))
+		regs->ARM_lr = iaddr + 4;
+
+	regs->ARM_pc = iaddr + 8 + disp;
+}
+
+static void simulate_blx1(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	long iaddr = (long)p->vaddr;
+	int disp = branch_displacement(insn);
+
+	regs->ARM_lr = iaddr + 4;
+	regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2);
+	regs->ARM_cpsr |= PSR_T_BIT;
+}
+
+static void simulate_blx2bx(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rm = insn & 0xf;
+	long rmv = regs->uregs[rm];
+
+	if (insn & (1 << 5))
+		regs->ARM_lr = (long)p->vaddr + 4;
+
+	regs->ARM_pc = rmv & ~0x1;
+	regs->ARM_cpsr &= ~PSR_T_BIT;
+	if (rmv & 0x1)
+		regs->ARM_cpsr |= PSR_T_BIT;
+}
+
+static void simulate_mrs(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rd = (insn >> 12) & 0xf;
+	unsigned long mask = 0xf8ff03df; /* Mask out execution state */
+	regs->uregs[rd] = regs->ARM_cpsr & mask;
+}
+
+static void simulate_mov_ipsp(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	regs->uregs[12] = regs->uregs[13];
+}
+
+static void
+emulate_ldrdstrd(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	unsigned long pc = (unsigned long)p->vaddr + 8;
+	int rt = (insn >> 12) & 0xf;
+	int rn = (insn >> 16) & 0xf;
+	int rm = insn & 0xf;
+
+	register unsigned long rtv asm("r0") = regs->uregs[rt];
+	register unsigned long rt2v asm("r1") = regs->uregs[rt+1];
+	register unsigned long rnv asm("r2") = (rn == 15) ? pc
+							  : regs->uregs[rn];
+	register unsigned long rmv asm("r3") = regs->uregs[rm];
+
+	__asm__ __volatile__ (
+		BLX("%[fn]")
+		: "=r" (rtv), "=r" (rt2v), "=r" (rnv)
+		: "0" (rtv), "1" (rt2v), "2" (rnv), "r" (rmv),
+		  [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	regs->uregs[rt] = rtv;
+	regs->uregs[rt+1] = rt2v;
+	if (is_writeback(insn))
+		regs->uregs[rn] = rnv;
+}
+
+static void
+emulate_ldr(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	unsigned long pc = (unsigned long)p->vaddr + 8;
+	int rt = (insn >> 12) & 0xf;
+	int rn = (insn >> 16) & 0xf;
+	int rm = insn & 0xf;
+
+	register unsigned long rtv asm("r0");
+	register unsigned long rnv asm("r2") = (rn == 15) ? pc
+							  : regs->uregs[rn];
+	register unsigned long rmv asm("r3") = regs->uregs[rm];
+
+	__asm__ __volatile__ (
+		BLX("%[fn]")
+		: "=r" (rtv), "=r" (rnv)
+		: "1" (rnv), "r" (rmv), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	if (rt == 15)
+		load_write_pc(rtv, regs);
+	else
+		regs->uregs[rt] = rtv;
+
+	if (is_writeback(insn))
+		regs->uregs[rn] = rnv;
+}
+
+static void
+emulate_str(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	unsigned long rtpc = (unsigned long)p->vaddr + str_pc_offset;
+	unsigned long rnpc = (unsigned long)p->vaddr + 8;
+	int rt = (insn >> 12) & 0xf;
+	int rn = (insn >> 16) & 0xf;
+	int rm = insn & 0xf;
+
+	register unsigned long rtv asm("r0") = (rt == 15) ? rtpc
+							  : regs->uregs[rt];
+	register unsigned long rnv asm("r2") = (rn == 15) ? rnpc
+							  : regs->uregs[rn];
+	register unsigned long rmv asm("r3") = regs->uregs[rm];
+
+	__asm__ __volatile__ (
+		BLX("%[fn]")
+		: "=r" (rnv)
+		: "r" (rtv), "0" (rnv), "r" (rmv), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	if (is_writeback(insn))
+		regs->uregs[rn] = rnv;
+}
+
+static void
+emulate_rd12rn16rm0rs8_rwflags(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	unsigned long pc = (unsigned long)p->vaddr + 8;
+	int rd = (insn >> 12) & 0xf;
+	int rn = (insn >> 16) & 0xf;
+	int rm = insn & 0xf;
+	int rs = (insn >> 8) & 0xf;
+
+	register unsigned long rdv asm("r0") = regs->uregs[rd];
+	register unsigned long rnv asm("r2") = (rn == 15) ? pc
+							  : regs->uregs[rn];
+	register unsigned long rmv asm("r3") = (rm == 15) ? pc
+							  : regs->uregs[rm];
+	register unsigned long rsv asm("r1") = regs->uregs[rs];
+	unsigned long cpsr = regs->ARM_cpsr;
+
+	__asm__ __volatile__ (
+		"msr	cpsr_fs, %[cpsr]	\n\t"
+		BLX("%[fn]")
+		"mrs	%[cpsr], cpsr		\n\t"
+		: "=r" (rdv), [cpsr] "=r" (cpsr)
+		: "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv),
+		  "1" (cpsr), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	if (rd == 15)
+		alu_write_pc(rdv, regs);
+	else
+		regs->uregs[rd] = rdv;
+	regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
+}
+
+static void
+emulate_rd12rn16rm0_rwflags_nopc(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rd = (insn >> 12) & 0xf;
+	int rn = (insn >> 16) & 0xf;
+	int rm = insn & 0xf;
+
+	register unsigned long rdv asm("r0") = regs->uregs[rd];
+	register unsigned long rnv asm("r2") = regs->uregs[rn];
+	register unsigned long rmv asm("r3") = regs->uregs[rm];
+	unsigned long cpsr = regs->ARM_cpsr;
+
+	__asm__ __volatile__ (
+		"msr	cpsr_fs, %[cpsr]	\n\t"
+		BLX("%[fn]")
+		"mrs	%[cpsr], cpsr		\n\t"
+		: "=r" (rdv), [cpsr] "=r" (cpsr)
+		: "0" (rdv), "r" (rnv), "r" (rmv),
+		  "1" (cpsr), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	regs->uregs[rd] = rdv;
+	regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
+}
+
+static void
+emulate_rd16rn12rm0rs8_rwflags_nopc(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rd = (insn >> 16) & 0xf;
+	int rn = (insn >> 12) & 0xf;
+	int rm = insn & 0xf;
+	int rs = (insn >> 8) & 0xf;
+
+	register unsigned long rdv asm("r2") = regs->uregs[rd];
+	register unsigned long rnv asm("r0") = regs->uregs[rn];
+	register unsigned long rmv asm("r3") = regs->uregs[rm];
+	register unsigned long rsv asm("r1") = regs->uregs[rs];
+	unsigned long cpsr = regs->ARM_cpsr;
+
+	__asm__ __volatile__ (
+		"msr	cpsr_fs, %[cpsr]	\n\t"
+		BLX("%[fn]")
+		"mrs	%[cpsr], cpsr		\n\t"
+		: "=r" (rdv), [cpsr] "=r" (cpsr)
+		: "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv),
+		  "1" (cpsr), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	regs->uregs[rd] = rdv;
+	regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
+}
+
+static void
+emulate_rd12rm0_noflags_nopc(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rd = (insn >> 12) & 0xf;
+	int rm = insn & 0xf;
+
+	register unsigned long rdv asm("r0") = regs->uregs[rd];
+	register unsigned long rmv asm("r3") = regs->uregs[rm];
+
+	__asm__ __volatile__ (
+		BLX("%[fn]")
+		: "=r" (rdv)
+		: "0" (rdv), "r" (rmv), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	regs->uregs[rd] = rdv;
+}
+
+static void
+emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct uprobe_probept *p, struct pt_regs *regs)
+{
+	uprobe_opcode_t insn = p->opcode;
+	int rdlo = (insn >> 12) & 0xf;
+	int rdhi = (insn >> 16) & 0xf;
+	int rn = insn & 0xf;
+	int rm = (insn >> 8) & 0xf;
+
+	register unsigned long rdlov asm("r0") = regs->uregs[rdlo];
+	register unsigned long rdhiv asm("r2") = regs->uregs[rdhi];
+	register unsigned long rnv asm("r3") = regs->uregs[rn];
+	register unsigned long rmv asm("r1") = regs->uregs[rm];
+	unsigned long cpsr = regs->ARM_cpsr;
+
+	__asm__ __volatile__ (
+		"msr	cpsr_fs, %[cpsr]	\n\t"
+		BLX("%[fn]")
+		"mrs	%[cpsr], cpsr		\n\t"
+		: "=r" (rdlov), "=r" (rdhiv), [cpsr] "=r" (cpsr)
+		: "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv),
+		  "2" (cpsr), [fn] "r" (p->arch_info.insn_fn)
+		: "lr", "memory", "cc"
+	);
+
+	regs->uregs[rdlo] = rdlov;
+	regs->uregs[rdhi] = rdhiv;
+	regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
+}
+
+/*
+ * For the instruction masking and comparisons in all the "space_*"
+ * functions below, Do _not_ rearrange the order of tests unless
+ * you're very, very sure of what you are doing.  For the sake of
+ * efficiency, the masks for some tests sometimes assume other test
+ * have been done prior to them so the number of patterns to test
+ * for an instruction set can be as broad as possible to reduce the
+ * number of tests needed.
+ */
+
+static const union decode_item arm_1111_table[] = {
+	/* Unconditional instructions					*/
+
+	/* memory hint		1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */
+	/* PLDI (immediate)	1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */
+	/* PLDW (immediate)	1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */
+	/* PLD (immediate)	1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_SIMULATE	(0xfe300000, 0xf4100000, uprobe_simulate_nop),
+
+	/* memory hint		1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */
+	/* PLDI (register)	1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */
+	/* PLDW (register)	1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */
+	/* PLD (register)	1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */
+	DECODE_SIMULATE	(0xfe300010, 0xf6100000, uprobe_simulate_nop),
+
+	/* BLX (immediate)	1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */
+	DECODE_SIMULATE	(0xfe000000, 0xfa000000, simulate_blx1),
+
+	/* CPS			1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */
+	/* SETEND		1111 0001 0000 0001 xxxx xxxx 0000 xxxx */
+	/* SRS			1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
+	/* RFE			1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
+
+	/* Coprocessor instructions... */
+	/* MCRR2		1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */
+	/* MRRC2		1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */
+	/* LDC2			1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
+	/* STC2			1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
+	/* CDP2			1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
+	/* MCR2			1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
+	/* MRC2			1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
+
+	/* Other unallocated instructions...				*/
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = {
+	/* Miscellaneous instructions					*/
+
+	/* MRS cpsr		cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */
+	DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs,
+						 REGS(0, NOPC, 0, 0, 0)),
+
+	/* BX			cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */
+	DECODE_SIMULATE	(0x0ff000f0, 0x01200010, simulate_blx2bx),
+
+	/* BLX (register)	cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */
+	DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx,
+						 REGS(0, 0, 0, 0, NOPC)),
+
+	/* CLZ			cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
+	DECODE_EMULATEX	(0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, NOPC)),
+
+	/* QADD			cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */
+	/* QSUB			cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */
+	/* QDADD		cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */
+	/* QDSUB		cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */
+	DECODE_EMULATEX	(0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+	/* BXJ			cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */
+	/* MSR			cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */
+	/* MRS spsr		cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */
+	/* BKPT			1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */
+	/* SMC			cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */
+	/* And unallocated instructions...				*/
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = {
+	/* Halfword multiply and multiply-accumulate			*/
+
+	/* SMLALxy		cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */
+	DECODE_EMULATEX	(0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
+						 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+	/* SMULWy		cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */
+	DECODE_OR	(0x0ff000b0, 0x012000a0),
+	/* SMULxy		cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */
+	DECODE_EMULATEX	(0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+	/* SMLAxy		cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */
+	DECODE_OR	(0x0ff00090, 0x01000080),
+	/* SMLAWy		cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */
+	DECODE_EMULATEX	(0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_0000_____1001_table[] = {
+	/* Multiply and multiply-accumulate				*/
+
+	/* MUL			cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */
+	/* MULS			cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */
+	DECODE_EMULATEX	(0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+	/* MLA			cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */
+	/* MLAS			cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */
+	DECODE_OR	(0x0fe000f0, 0x00200090),
+	/* MLS			cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */
+	DECODE_EMULATEX	(0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+	/* UMAAL		cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */
+	DECODE_OR	(0x0ff000f0, 0x00400090),
+	/* UMULL		cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */
+	/* UMULLS		cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */
+	/* UMLAL		cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */
+	/* UMLALS		cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */
+	/* SMULL		cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */
+	/* SMULLS		cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */
+	/* SMLAL		cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */
+	/* SMLALS		cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */
+	DECODE_EMULATEX	(0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
+						 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_____1001_table[] = {
+	/* Synchronization primitives					*/
+
+	/* SMP/SWPB		cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */
+	DECODE_EMULATEX	(0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+	/* LDREX/STREX{,D,B,H}	cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */
+	/* And unallocated instructions...				*/
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_000x_____1xx1_table[] = {
+	/* Extra load/store instructions				*/
+
+	/* STRHT		cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */
+	/* ???			cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */
+	/* LDRHT		cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */
+	/* LDRSBT		cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */
+	/* LDRSHT		cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_REJECT	(0x0f200090, 0x00200090),
+
+	/* LDRD/STRD lr,pc,{...	cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */
+	DECODE_REJECT	(0x0e10e0d0, 0x0000e0d0),
+
+	/* LDRD (register)	cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */
+	/* STRD (register)	cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_EMULATEX	(0x0e5000d0, 0x000000d0, emulate_ldrdstrd,
+						 REGS(NOPCWB, NOPCX, 0, 0, NOPC)),
+
+	/* LDRD (immediate)	cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */
+	/* STRD (immediate)	cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_EMULATEX	(0x0e5000d0, 0x004000d0, emulate_ldrdstrd,
+						 REGS(NOPCWB, NOPCX, 0, 0, 0)),
+
+	/* STRH (register)	cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */
+	DECODE_EMULATEX	(0x0e5000f0, 0x000000b0, emulate_str,
+						 REGS(NOPCWB, NOPC, 0, 0, NOPC)),
+
+	/* LDRH (register)	cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */
+	/* LDRSB (register)	cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */
+	/* LDRSH (register)	cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_EMULATEX	(0x0e500090, 0x00100090, emulate_ldr,
+						 REGS(NOPCWB, NOPC, 0, 0, NOPC)),
+
+	/* STRH (immediate)	cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */
+	DECODE_EMULATEX	(0x0e5000f0, 0x004000b0, emulate_str,
+						 REGS(NOPCWB, NOPC, 0, 0, 0)),
+
+	/* LDRH (immediate)	cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */
+	/* LDRSB (immediate)	cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */
+	/* LDRSH (immediate)	cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_EMULATEX	(0x0e500090, 0x00500090, emulate_ldr,
+						 REGS(NOPCWB, NOPC, 0, 0, 0)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_000x_table[] = {
+	/* Data-processing (register)					*/
+
+	/* <op>S PC, ...	cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */
+	DECODE_REJECT	(0x0e10f000, 0x0010f000),
+
+	/* MOV IP, SP		1110 0001 1010 0000 1100 0000 0000 1101 */
+	DECODE_SIMULATE	(0xffffffff, 0xe1a0c00d, simulate_mov_ipsp),
+
+	/* TST (register)	cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */
+	/* TEQ (register)	cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */
+	/* CMP (register)	cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */
+	/* CMN (register)	cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */
+	DECODE_EMULATEX	(0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(ANY, 0, 0, 0, ANY)),
+
+	/* MOV (register)	cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */
+	/* MVN (register)	cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */
+	DECODE_EMULATEX	(0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(0, ANY, 0, 0, ANY)),
+
+	/* AND (register)	cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */
+	/* EOR (register)	cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */
+	/* SUB (register)	cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */
+	/* RSB (register)	cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */
+	/* ADD (register)	cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */
+	/* ADC (register)	cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */
+	/* SBC (register)	cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */
+	/* RSC (register)	cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */
+	/* ORR (register)	cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */
+	/* BIC (register)	cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */
+	DECODE_EMULATEX	(0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(ANY, ANY, 0, 0, ANY)),
+
+	/* TST (reg-shift reg)	cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */
+	/* TEQ (reg-shift reg)	cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */
+	/* CMP (reg-shift reg)	cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */
+	/* CMN (reg-shift reg)	cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */
+	DECODE_EMULATEX	(0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(ANY, 0, NOPC, 0, ANY)),
+
+	/* MOV (reg-shift reg)	cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */
+	/* MVN (reg-shift reg)	cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */
+	DECODE_EMULATEX	(0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(0, ANY, NOPC, 0, ANY)),
+
+	/* AND (reg-shift reg)	cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */
+	/* EOR (reg-shift reg)	cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */
+	/* SUB (reg-shift reg)	cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */
+	/* RSB (reg-shift reg)	cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */
+	/* ADD (reg-shift reg)	cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */
+	/* ADC (reg-shift reg)	cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */
+	/* SBC (reg-shift reg)	cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */
+	/* RSC (reg-shift reg)	cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */
+	/* ORR (reg-shift reg)	cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */
+	/* BIC (reg-shift reg)	cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */
+	DECODE_EMULATEX	(0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(ANY, ANY, NOPC, 0, ANY)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_001x_table[] = {
+	/* Data-processing (immediate)					*/
+
+	/* MOVW			cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
+	/* MOVT			cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, 0)),
+
+	/* YIELD		cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
+	DECODE_OR	(0x0fff00ff, 0x03200001),
+	/* SEV			cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
+	DECODE_EMULATE	(0x0fff00ff, 0x03200004, uprobe_emulate_none),
+	/* NOP			cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
+	/* WFE			cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
+	/* WFI			cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
+	DECODE_SIMULATE	(0x0fff00fc, 0x03200000, uprobe_simulate_nop),
+	/* DBG			cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
+	/* unallocated hints	cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
+	/* MSR (immediate)	cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_REJECT	(0x0fb00000, 0x03200000),
+
+	/* <op>S PC, ...	cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
+	DECODE_REJECT	(0x0e10f000, 0x0210f000),
+
+	/* TST (immediate)	cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
+	/* TEQ (immediate)	cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
+	/* CMP (immediate)	cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
+	/* CMN (immediate)	cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(ANY, 0, 0, 0, 0)),
+
+	/* MOV (immediate)	cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
+	/* MVN (immediate)	cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(0, ANY, 0, 0, 0)),
+
+	/* AND (immediate)	cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
+	/* EOR (immediate)	cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
+	/* SUB (immediate)	cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
+	/* RSB (immediate)	cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
+	/* ADD (immediate)	cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
+	/* ADC (immediate)	cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
+	/* SBC (immediate)	cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
+	/* RSC (immediate)	cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
+	/* ORR (immediate)	cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
+	/* BIC (immediate)	cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags,
+						 REGS(ANY, ANY, 0, 0, 0)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_0110_____xxx1_table[] = {
+	/* Media instructions						*/
+
+	/* SEL			cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */
+	DECODE_EMULATEX	(0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+	/* SSAT			cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */
+	/* USAT			cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */
+	DECODE_OR(0x0fa00030, 0x06a00010),
+	/* SSAT16		cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */
+	/* USAT16		cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */
+	DECODE_EMULATEX	(0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(0, NOPC, 0, 0, NOPC)),
+
+	/* REV			cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */
+	/* REV16		cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */
+	/* RBIT			cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */
+	/* REVSH		cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */
+	DECODE_EMULATEX	(0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, NOPC)),
+
+	/* ???			cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */
+	DECODE_REJECT	(0x0fb00010, 0x06000010),
+	/* ???			cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */
+	DECODE_REJECT	(0x0f8000f0, 0x060000b0),
+	/* ???			cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */
+	DECODE_REJECT	(0x0f8000f0, 0x060000d0),
+	/* SADD16		cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */
+	/* SADDSUBX		cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */
+	/* SSUBADDX		cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */
+	/* SSUB16		cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */
+	/* SADD8		cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */
+	/* SSUB8		cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */
+	/* QADD16		cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */
+	/* QADDSUBX		cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */
+	/* QSUBADDX		cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */
+	/* QSUB16		cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */
+	/* QADD8		cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */
+	/* QSUB8		cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */
+	/* SHADD16		cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */
+	/* SHADDSUBX		cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */
+	/* SHSUBADDX		cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */
+	/* SHSUB16		cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */
+	/* SHADD8		cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */
+	/* SHSUB8		cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */
+	/* UADD16		cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */
+	/* UADDSUBX		cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */
+	/* USUBADDX		cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */
+	/* USUB16		cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */
+	/* UADD8		cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */
+	/* USUB8		cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */
+	/* UQADD16		cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */
+	/* UQADDSUBX		cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */
+	/* UQSUBADDX		cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */
+	/* UQSUB16		cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */
+	/* UQADD8		cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */
+	/* UQSUB8		cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */
+	/* UHADD16		cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */
+	/* UHADDSUBX		cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */
+	/* UHSUBADDX		cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */
+	/* UHSUB16		cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */
+	/* UHADD8		cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */
+	/* UHSUB8		cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_EMULATEX	(0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+	/* PKHBT		cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */
+	/* PKHTB		cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */
+	DECODE_EMULATEX	(0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+	/* ???			cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */
+	/* ???			cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */
+	DECODE_REJECT	(0x0fb000f0, 0x06900070),
+
+	/* SXTB16		cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */
+	/* SXTB			cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */
+	/* SXTH			cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */
+	/* UXTB16		cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */
+	/* UXTB			cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */
+	/* UXTH			cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */
+	DECODE_EMULATEX	(0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, NOPC)),
+
+	/* SXTAB16		cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */
+	/* SXTAB		cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */
+	/* SXTAH		cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */
+	/* UXTAB16		cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */
+	/* UXTAB		cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */
+	/* UXTAH		cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */
+	DECODE_EMULATEX	(0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc,
+						 REGS(NOPCX, NOPC, 0, 0, NOPC)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_0111_____xxx1_table[] = {
+	/* Media instructions						*/
+
+	/* UNDEFINED		cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */
+	DECODE_REJECT	(0x0ff000f0, 0x07f000f0),
+
+	/* SMLALD		cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */
+	/* SMLSLD		cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */
+	DECODE_EMULATEX	(0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
+						 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+	/* SMUAD		cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */
+	/* SMUSD		cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */
+	DECODE_OR	(0x0ff0f090, 0x0700f010),
+	/* SMMUL		cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */
+	DECODE_OR	(0x0ff0f0d0, 0x0750f010),
+	/* USAD8		cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */
+	DECODE_EMULATEX	(0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+	/* SMLAD		cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */
+	/* SMLSD		cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */
+	DECODE_OR	(0x0ff00090, 0x07000010),
+	/* SMMLA		cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */
+	DECODE_OR	(0x0ff000d0, 0x07500010),
+	/* USADA8		cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */
+	DECODE_EMULATEX	(0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, NOPCX, NOPC, 0, NOPC)),
+
+	/* SMMLS		cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */
+	DECODE_EMULATEX	(0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc,
+						 REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+	/* SBFX			cccc 0111 101x xxxx xxxx xxxx x101 xxxx */
+	/* UBFX			cccc 0111 111x xxxx xxxx xxxx x101 xxxx */
+	DECODE_EMULATEX	(0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, NOPC)),
+
+	/* BFC			cccc 0111 110x xxxx xxxx xxxx x001 1111 */
+	DECODE_EMULATEX	(0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, 0)),
+
+	/* BFI			cccc 0111 110x xxxx xxxx xxxx x001 xxxx */
+	DECODE_EMULATEX	(0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc,
+						 REGS(0, NOPC, 0, 0, NOPCX)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_01xx_table[] = {
+	/* Load/store word and unsigned byte				*/
+
+	/* LDRB/STRB pc,[...]	cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */
+	DECODE_REJECT	(0x0c40f000, 0x0440f000),
+
+	/* STRT			cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */
+	/* LDRT			cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */
+	/* STRBT		cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */
+	/* LDRBT		cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_REJECT	(0x0d200000, 0x04200000),
+
+	/* STR (immediate)	cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */
+	/* STRB (immediate)	cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0e100000, 0x04000000, emulate_str,
+						 REGS(NOPCWB, ANY, 0, 0, 0)),
+
+	/* LDR (immediate)	cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */
+	/* LDRB (immediate)	cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0e100000, 0x04100000, emulate_ldr,
+						 REGS(NOPCWB, ANY, 0, 0, 0)),
+
+	/* STR (register)	cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */
+	/* STRB (register)	cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0e100000, 0x06000000, emulate_str,
+						 REGS(NOPCWB, ANY, 0, 0, NOPC)),
+
+	/* LDR (register)	cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */
+	/* LDRB (register)	cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_EMULATEX	(0x0e100000, 0x06100000, emulate_ldr,
+						 REGS(NOPCWB, ANY, 0, 0, NOPC)),
+
+	DECODE_END
+};
+
+static const union decode_item arm_cccc_100x_table[] = {
+	/* Block data transfer instructions				*/
+
+	/* LDM			cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
+	/* STM			cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */
+	DECODE_CUSTOM	(0x0e400000, 0x08000000, uprobe_decode_ldmstm),
+
+	/* STM (user registers)	cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
+	/* LDM (user registers)	cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */
+	/* LDM (exception ret)	cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */
+	DECODE_END
+};
+
+const union decode_item uprobe_decode_arm_table[] = {
+	/*
+	 * Unconditional instructions
+	 *			1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx
+	 */
+	DECODE_TABLE	(0xf0000000, 0xf0000000, arm_1111_table),
+
+	/*
+	 * Miscellaneous instructions
+	 *			cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx
+	 */
+	DECODE_TABLE	(0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table),
+
+	/*
+	 * Halfword multiply and multiply-accumulate
+	 *			cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx
+	 */
+	DECODE_TABLE	(0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table),
+
+	/*
+	 * Multiply and multiply-accumulate
+	 *			cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx
+	 */
+	DECODE_TABLE	(0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table),
+
+	/*
+	 * Synchronization primitives
+	 *			cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx
+	 */
+	DECODE_TABLE	(0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table),
+
+	/*
+	 * Extra load/store instructions
+	 *			cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx
+	 */
+	DECODE_TABLE	(0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table),
+
+	/*
+	 * Data-processing (register)
+	 *			cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx
+	 * Data-processing (register-shifted register)
+	 *			cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx
+	 */
+	DECODE_TABLE	(0x0e000000, 0x00000000, arm_cccc_000x_table),
+
+	/*
+	 * Data-processing (immediate)
+	 *			cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
+	 */
+	DECODE_TABLE	(0x0e000000, 0x02000000, arm_cccc_001x_table),
+
+	/*
+	 * Media instructions
+	 *			cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx
+	 */
+	DECODE_TABLE	(0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table),
+	DECODE_TABLE	(0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table),
+
+	/*
+	 * Load/store word and unsigned byte
+	 *			cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx
+	 */
+	DECODE_TABLE	(0x0c000000, 0x04000000, arm_cccc_01xx_table),
+
+	/*
+	 * Block data transfer instructions
+	 *			cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx
+	 */
+	DECODE_TABLE	(0x0e000000, 0x08000000, arm_cccc_100x_table),
+
+	/* B			cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */
+	/* BL			cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */
+	DECODE_SIMULATE	(0x0e000000, 0x0a000000, simulate_bbl),
+
+	/*
+	 * Supervisor Call, and coprocessor instructions
+	 */
+
+	/* MCRR			cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */
+	/* MRRC			cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */
+	/* LDC			cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
+	/* STC			cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
+	/* CDP			cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
+	/* MCR			cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
+	/* MRC			cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
+	/* SVC			cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */
+	DECODE_REJECT	(0x0c000000, 0x0c000000),
+
+	DECODE_END
+};
+
+/*
+ * Prepare an instruction slot to receive an instruction for emulating.
+ * This is done by placing a subroutine return after the location where the
+ * instruction will be placed. We also modify ARM instructions to be
+ * unconditional as the condition code will already be checked before any
+ * emulation handler is called.
+ */
+static uprobe_opcode_t
+prepare_emulated_insn(uprobe_opcode_t insn, struct uprobe_probept_arch_info *ai)
+{
+	ai->insn[1] = 0xe1a0f00e; /* mov pc, lr */
+
+	/* Make an ARM instruction unconditional */
+	if (insn < 0xe0000000)
+		insn = (insn | 0xe0000000) & ~0x10000000;
+	return insn;
+}
+
+/*
+ * Write a (probably modified) instruction into the slot previously prepared by
+ * prepare_emulated_insn
+ */
+static void
+set_emulated_insn(uprobe_opcode_t insn, struct uprobe_probept_arch_info *ai)
+{
+	ai->insn[0] = insn;
+}
+
+/*
+ * When we modify the register numbers encoded in an instruction to be emulated,
+ * the new values come from this define. For ARM and 32-bit Thumb instructions
+ * this gives...
+ *
+ *	bit position	  16  12   8   4   0
+ *	---------------+---+---+---+---+---+
+ *	register	 r2  r0  r1  --  r3
+ */
+#define INSN_NEW_BITS		0x00020103
+
+/* Each nibble has same value as that at INSN_NEW_BITS bit 16 */
+#define INSN_SAMEAS16_BITS	0x22222222
+
+/*
+ * Validate and modify each of the registers encoded in an instruction.
+ *
+ * Each nibble in regs contains a value from enum decode_reg_type. For each
+ * non-zero value, the corresponding nibble in pinsn is validated and modified
+ * according to the type.
+ */
+static bool decode_regs(uprobe_opcode_t* pinsn, u32 regs)
+{
+	uprobe_opcode_t insn = *pinsn;
+	uprobe_opcode_t mask = 0xf; /* Start at least significant nibble */
+
+	for (; regs != 0; regs >>= 4, mask <<= 4) {
+
+		uprobe_opcode_t new_bits = INSN_NEW_BITS;
+
+		switch (regs & 0xf) {
+
+		case REG_TYPE_NONE:
+			/* Nibble not a register, skip to next */
+			continue;
+
+		case REG_TYPE_ANY:
+			/* Any register is allowed */
+			break;
+
+		case REG_TYPE_SAMEAS16:
+			/* Replace register with same as at bit position 16 */
+			new_bits = INSN_SAMEAS16_BITS;
+			break;
+
+		case REG_TYPE_SP:
+			/* Only allow SP (R13) */
+			if ((insn ^ 0xdddddddd) & mask)
+				goto reject;
+			break;
+
+		case REG_TYPE_PC:
+			/* Only allow PC (R15) */
+			if ((insn ^ 0xffffffff) & mask)
+				goto reject;
+			break;
+
+		case REG_TYPE_NOSP:
+			/* Reject SP (R13) */
+			if (((insn ^ 0xdddddddd) & mask) == 0)
+				goto reject;
+			break;
+
+		case REG_TYPE_NOSPPC:
+		case REG_TYPE_NOSPPCX:
+			/* Reject SP and PC (R13 and R15) */
+			if (((insn ^ 0xdddddddd) & 0xdddddddd & mask) == 0)
+				goto reject;
+			break;
+
+		case REG_TYPE_NOPCWB:
+			if (!is_writeback(insn))
+				break; /* No writeback, so any register is OK */
+			/* fall through... */
+		case REG_TYPE_NOPC:
+		case REG_TYPE_NOPCX:
+			/* Reject PC (R15) */
+			if (((insn ^ 0xffffffff) & mask) == 0)
+				goto reject;
+			break;
+		}
+
+		/* Replace value of nibble with new register number... */
+		insn &= ~mask;
+		insn |= new_bits & mask;
+	}
+
+	*pinsn = insn;
+	return true;
+
+reject:
+	return false;
+}
+
+static const int decode_struct_sizes[NUM_DECODE_TYPES] = {
+	[DECODE_TYPE_TABLE]	= sizeof(struct decode_table),
+	[DECODE_TYPE_CUSTOM]	= sizeof(struct decode_custom),
+	[DECODE_TYPE_SIMULATE]	= sizeof(struct decode_simulate),
+	[DECODE_TYPE_EMULATE]	= sizeof(struct decode_emulate),
+	[DECODE_TYPE_OR]	= sizeof(struct decode_or),
+	[DECODE_TYPE_REJECT]	= sizeof(struct decode_reject)
+};
+
+/*
+ * uprobe_decode_insn operates on data tables in order to decode an ARM
+ * architecture instruction onto which a uprobe has been placed.
+ *
+ * These instruction decoding tables are a concatenation of entries each
+ * of which consist of one of the following structs:
+ *
+ *	decode_table
+ *	decode_custom
+ *	decode_simulate
+ *	decode_emulate
+ *	decode_or
+ *	decode_reject
+ *
+ * Each of these starts with a struct decode_header which has the following
+ * fields:
+ *
+ *	type_regs
+ *	mask
+ *	value
+ *
+ * The least significant DECODE_TYPE_BITS of type_regs contains a value
+ * from enum decode_type, this indicates which of the decode_* structs
+ * the entry contains. The value DECODE_TYPE_END indicates the end of the
+ * table.
+ *
+ * When the table is parsed, each entry is checked in turn to see if it
+ * matches the instruction to be decoded using the test:
+ *
+ *	(insn & mask) == value
+ *
+ * If no match is found before the end of the table is reached then decoding
+ * fails with INSN_REJECTED.
+ *
+ * When a match is found, decode_regs() is called to validate and modify each
+ * of the registers encoded in the instruction; the data it uses to do this
+ * is (type_regs >> DECODE_TYPE_BITS). A validation failure will cause decoding
+ * to fail with INSN_REJECTED.
+ *
+ * Once the instruction has passed the above tests, further processing
+ * depends on the type of the table entry's decode struct.
+ *
+ */
+int
+uprobe_decode_insn(uprobe_opcode_t insn, struct uprobe_probept_arch_info *ai,
+				const union decode_item *table)
+{
+	const struct decode_header *h = (struct decode_header *)table;
+	const struct decode_header *next;
+	bool matched = false;
+
+	insn = prepare_emulated_insn(insn, ai);
+
+	for (;; h = next) {
+		enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+		u32 regs = h->type_regs.bits >> DECODE_TYPE_BITS;
+
+		if (type == DECODE_TYPE_END)
+			return INSN_REJECTED;
+
+		next = (struct decode_header *)
+				((uintptr_t)h + decode_struct_sizes[type]);
+
+		if (!matched && (insn & h->mask.bits) != h->value.bits)
+			continue;
+
+		if (!decode_regs(&insn, regs))
+			return INSN_REJECTED;
+
+		switch (type) {
+
+		case DECODE_TYPE_TABLE: {
+			struct decode_table *d = (struct decode_table *)h;
+			next = (struct decode_header *)d->table.table;
+			break;
+		}
+
+		case DECODE_TYPE_CUSTOM: {
+			struct decode_custom *d = (struct decode_custom *)h;
+			return (*d->decoder.decoder)(insn, ai);
+		}
+
+		case DECODE_TYPE_SIMULATE: {
+			struct decode_simulate *d = (struct decode_simulate *)h;
+			ai->insn_handler = d->handler.handler;
+			return INSN_GOOD_NO_SLOT;
+		}
+
+		case DECODE_TYPE_EMULATE: {
+			struct decode_emulate *d = (struct decode_emulate *)h;
+			ai->insn_handler = d->handler.handler;
+			set_emulated_insn(insn, ai);
+			return INSN_GOOD;
+		}
+
+		case DECODE_TYPE_OR:
+			matched = true;
+			break;
+
+		case DECODE_TYPE_REJECT:
+		default:
+			return INSN_REJECTED;
+		}
+		}
+	}
+/* Return:
+ *   INSN_REJECTED     If instruction is one not allowed to uprobe,
+ *   INSN_GOOD         If instruction is supported and uses instruction slot,
+ *   INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
+ *
+ * For instructions we don't want to uprobe (INSN_REJECTED return result):
+ *   These are generally ones that modify the processor state making
+ *   them "hard" to simulate such as switches processor modes or
+ *   make accesses in alternate modes.  Any of these could be simulated
+ *   if the work was put into it, but low return considering they
+ *   should also be very rare.
+ */
+enum uprobe_insn
+arm_uprobe_decode_insn(uprobe_opcode_t insn,
+		struct uprobe_probept_arch_info *ai)
+{
+	ai->insn_check_cc = uprobe_condition_checks[insn>>28];
+	return uprobe_decode_insn(insn, ai, uprobe_decode_arm_table);
+}
+
+static int arch_validate_probed_insn(struct uprobe_probept *ppt,
+		struct task_struct *tsk)
+{
+	uprobe_opcode_t insn = *ppt->insn;
+
+	if (ppt->vaddr & 0x3)
+		return -EINVAL;
+
+	arm_uprobe_decode_init();
+	switch (arm_uprobe_decode_insn(insn, &ppt->arch_info)) {
+	case INSN_REJECTED:
+		return -EINVAL;
+
+	case INSN_GOOD:
+		ppt->arch_info.insn_fn = (uprobe_insn_fn_t *)
+			ppt->arch_info.insn;
+		flush_icache_range((unsigned long)ppt->arch_info.insn,
+				   (unsigned long)ppt->arch_info.insn +
+				   	sizeof(ppt->arch_info.insn[0]) *
+					MAX_INSN_SIZE);
+		break;
+
+	case INSN_GOOD_NO_SLOT:
+		break;
+	}
+
+	return 0;
+}
+
+static int uprobe_emulate_insn(struct pt_regs *regs,
+		struct uprobe_probept *ppt)
+{
+	if (ppt->arch_info.insn_handler) {
+		regs->ARM_pc += 4;
+		ppt->arch_info.insn_handler(ppt, regs);
+		return 1;
+	}
+	return 0;
+}
+
diff --git a/runtime/uprobes2/uprobes_arm.h b/runtime/uprobes2/uprobes_arm.h
new file mode 100644
index 0000000..a71c73c
--- /dev/null
+++ b/runtime/uprobes2/uprobes_arm.h
@@ -0,0 +1,114 @@
+#ifndef _ASM_UPROBES_H
+#define _ASM_UPROBES_H
+/*
+ *  Userspace Probes (UProbes)
+ *  uprobes.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright 2011 (C) Mentor Graphics Corporation
+ */
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/sched.h>
+#include <asm/thread_info.h>
+#include <asm/cacheflush.h>
+#include <asm/smp_plat.h>
+#include <asm/uaccess.h>
+#include <asm/tlbflush.h>
+
+/* Normally defined in Kconfig */
+#define CONFIG_URETPROBES 1
+
+typedef u32 uprobe_opcode_t;
+#define BREAKPOINT_INSTRUCTION 0xe7ffdefe
+#define BP_INSN_SIZE 4
+#define MAX_UINSN_BYTES 4
+
+#define BREAKPOINT_SIGNAL SIGILL
+#define SSTEP_SIGNAL SIGILL
+
+/* Architecture specific switch for where the IP points after a bp hit */
+#define ARCH_BP_INST_PTR(inst_ptr)	(inst_ptr)
+
+struct uprobe_probept;
+
+typedef void (uprobe_insn_handler_t)(struct uprobe_probept *, struct pt_regs *);
+typedef unsigned long (uprobe_check_cc)(unsigned long);
+typedef void (uprobe_insn_fn_t)(void);
+
+#define MAX_INSN_SIZE 2
+struct uprobe_probept_arch_info {
+	uprobe_opcode_t			insn[MAX_INSN_SIZE];
+	uprobe_insn_handler_t		*insn_handler;
+	uprobe_check_cc			*insn_check_cc;
+	uprobe_insn_fn_t		*insn_fn;
+};
+
+struct uprobe_task_arch_info {};
+
+struct uprobe_probept;
+struct uprobe_task;
+
+static int arch_validate_probed_insn(struct uprobe_probept *ppt,
+		struct task_struct *tsk);
+
+static inline unsigned long arch_get_probept(struct pt_regs *regs)
+{
+	return regs->ARM_pc;
+}
+
+
+static inline void arch_reset_ip_for_sstep(struct pt_regs *regs)
+{
+}
+
+
+static long arch_hijack_uret_addr(unsigned long trampoline_addr,
+		struct pt_regs *regs, struct uprobe_task *utask)
+{
+	unsigned long orig_ret_addr = regs->ARM_lr;
+
+	regs->ARM_lr = trampoline_addr;
+	return orig_ret_addr;
+}
+
+static inline void arch_restore_uret_addr(unsigned long ret_addr,
+		struct pt_regs *regs)
+{
+	regs->ARM_pc = ret_addr;
+}
+
+static inline unsigned long arch_get_cur_sp(struct pt_regs *regs)
+{
+	return regs->ARM_sp;
+}
+
+static inline unsigned long arch_predict_sp_at_ret(struct pt_regs *regs,
+		struct task_struct *tsk)
+{
+	return regs->ARM_sp;
+}
+
+/* copy_to_user_page() is not exported.  Implement our own version.*/
+#ifndef copy_to_user_page
+#define copy_to_user_page(vma, page, vaddr, dst, src, len)	\
+	do {							\
+		memcpy(dst, src, len);				\
+		flush_icache_range((unsigned long)dst,		\
+				   (unsigned long)dst + len);	\
+	} while (0)
+#endif
+
+#endif				/* _ASM_UPROBES_H */
-- 
1.7.0.4


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