Stage 2 of structural changes for support of THUMB2.  No logic changes.
diff --git a/vm/compiler/codegen/arm/Assemble.c b/vm/compiler/codegen/arm/Assemble.c
new file mode 100644
index 0000000..f9961ce
--- /dev/null
+++ b/vm/compiler/codegen/arm/Assemble.c
@@ -0,0 +1,941 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Dalvik.h"
+#include "libdex/OpCode.h"
+#include "dexdump/OpCodeNames.h"
+
+#include "../../CompilerInternals.h"
+#include "ArmLIR.h"
+#include <unistd.h>             /* for cacheflush */
+
+/*
+ * opcode: ArmOpCode enum
+ * skeleton: pre-designated bit-pattern for this opcode
+ * ds: dest start bit position
+ * de: dest end bit position
+ * s1s: src1 start bit position
+ * s1e: src1 end bit position
+ * s2s: src2 start bit position
+ * s2e: src2 end bit position
+ * operands: number of operands (for sanity check purposes)
+ * name: mnemonic name
+ * fmt: for pretty-prining
+ */
+#define ENCODING_MAP(opcode, skeleton, ds, de, s1s, s1e, s2s, s2e, operands, \
+                     name, fmt, size) \
+        {skeleton, {{ds, de}, {s1s, s1e}, {s2s, s2e}}, opcode, operands, name, \
+         fmt, size}
+
+/* Instruction dump string format keys: !pf, where "!" is the start
+ * of the key, "p" is which numeric operand to use and "f" is the
+ * print format.
+ *
+ * [p]ositions:
+ *     0 -> operands[0] (dest)
+ *     1 -> operands[1] (src1)
+ *     2 -> operands[2] (src2)
+ *
+ * [f]ormats:
+ *     h -> 4-digit hex
+ *     d -> decimal
+ *     D -> decimal+8 (used to convert 3-bit regnum field to high reg)
+ *     E -> decimal*4
+ *     F -> decimal*2
+ *     c -> branch condition (beq, bne, etc.)
+ *     t -> pc-relative target
+ *     u -> 1st half of bl[x] target
+ *     v -> 2nd half ob bl[x] target
+ *     R -> register list
+ *
+ *  [!] escape.  To insert "!", use "!!"
+ */
+/* NOTE: must be kept in sync with enum ArmOpcode from ArmLIR.h */
+ArmEncodingMap EncodingMap[ARM_LAST] = {
+    ENCODING_MAP(ARM_16BIT_DATA,    0x0000, 15, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP,
+                 "data", "0x!0h(!0d)", 1),
+    ENCODING_MAP(THUMB_ADC,           0x4140, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "adc", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_ADD_RRI3,      0x1c00, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, r!1d, #!2d", 1),
+    ENCODING_MAP(THUMB_ADD_RI8,       0x3000, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, r!0d, #!1d", 1),
+    ENCODING_MAP(THUMB_ADD_RRR,       0x1800, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, r!1d, r!2d", 1),
+    ENCODING_MAP(THUMB_ADD_RR_LH,     0x4440, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "add",
+                 "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_ADD_RR_HL,     0x4480, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_ADD_RR_HH,     0x44c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_ADD_PC_REL,    0xa000, 10, 8, 7, 0, -1, -1,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, pc, #!1E", 1),
+    ENCODING_MAP(THUMB_ADD_SP_REL,    0xa800, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "add", "r!0d, sp, #!1E", 1),
+    ENCODING_MAP(THUMB_ADD_SPI7,      0xb000, 6, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP | CLOBBER_DEST,
+                 "add", "sp, #!0d*4", 1),
+    ENCODING_MAP(THUMB_AND_RR,        0x4000, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "and", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_ASR,           0x1000, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "asr", "r!0d, r!1d, #!2d", 1),
+    ENCODING_MAP(THUMB_ASRV,          0x4100, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "asr", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_B_COND,        0xd000, 7, 0, 11, 8, -1, -1,
+                 IS_BINARY_OP | IS_BRANCH,
+                 "!1c", "!0t", 1),
+    ENCODING_MAP(THUMB_B_UNCOND,      0xe000, 10, 0, -1, -1, -1, -1,
+                 NO_OPERAND | IS_BRANCH,
+                 "b", "!0t", 1),
+    ENCODING_MAP(THUMB_BIC,           0x4380, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "bic", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_BKPT,          0xbe00, 7, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP | IS_BRANCH,
+                 "bkpt", "!0d", 1),
+    ENCODING_MAP(THUMB_BLX_1,         0xf000, 10, 0, -1, -1, -1, -1,
+                 IS_BINARY_OP | IS_BRANCH,
+                 "blx_1", "!0u", 1),
+    ENCODING_MAP(THUMB_BLX_2,         0xe800, 10, 0, -1, -1, -1, -1,
+                 IS_BINARY_OP | IS_BRANCH,
+                 "blx_2", "!0v", 1),
+    ENCODING_MAP(THUMB_BL_1,          0xf000, 10, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP | IS_BRANCH,
+                 "bl_1", "!0u", 1),
+    ENCODING_MAP(THUMB_BL_2,          0xf800, 10, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP | IS_BRANCH,
+                 "bl_2", "!0v", 1),
+    ENCODING_MAP(THUMB_BLX_R,         0x4780, 6, 3, -1, -1, -1, -1,
+                 IS_UNARY_OP | IS_BRANCH,
+                 "blx", "r!0d", 1),
+    ENCODING_MAP(THUMB_BX,            0x4700, 6, 3, -1, -1, -1, -1,
+                 IS_UNARY_OP | IS_BRANCH,
+                 "bx", "r!0d", 1),
+    ENCODING_MAP(THUMB_CMN,           0x42c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP,
+                 "cmn", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_CMP_RI8,       0x2800, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP,
+                 "cmp", "r!0d, #!1d", 1),
+    ENCODING_MAP(THUMB_CMP_RR,        0x4280, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP,
+                 "cmp", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_CMP_LH,        0x4540, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP,
+                 "cmp", "r!0d, r!1D", 1),
+    ENCODING_MAP(THUMB_CMP_HL,        0x4580, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP,
+                 "cmp", "r!0D, r!1d", 1),
+    ENCODING_MAP(THUMB_CMP_HH,        0x45c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP,
+                 "cmp", "r!0D, r!1D", 1),
+    ENCODING_MAP(THUMB_EOR,           0x4040, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "eor", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_LDMIA,         0xc800, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST | CLOBBER_SRC1,
+                 "ldmia", "r!0d!!, <!1R>", 1),
+    ENCODING_MAP(THUMB_LDR_RRI5,      0x6800, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldr", "r!0d, [r!1d, #!2E]", 1),
+    ENCODING_MAP(THUMB_LDR_RRR,       0x5800, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldr", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_LDR_PC_REL,    0x4800, 10, 8, 7, 0, -1, -1,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldr", "r!0d, [pc, #!1E]", 1),
+    ENCODING_MAP(THUMB_LDR_SP_REL,    0x9800, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "ldr", "r!0d, [sp, #!1E]", 1),
+    ENCODING_MAP(THUMB_LDRB_RRI5,     0x7800, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldrb", "r!0d, [r!1d, #2d]", 1),
+    ENCODING_MAP(THUMB_LDRB_RRR,      0x5c00, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldrb", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_LDRH_RRI5,     0x8800, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldrh", "r!0d, [r!1d, #!2F]", 1),
+    ENCODING_MAP(THUMB_LDRH_RRR,      0x5a00, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldrh", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_LDRSB_RRR,     0x5600, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldrsb", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_LDRSH_RRR,     0x5e00, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "ldrsh", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_LSL,           0x0000, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "lsl", "r!0d, r!1d, #!2d", 1),
+    ENCODING_MAP(THUMB_LSLV,          0x4080, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "lsl", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_LSR,           0x0800, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "lsr", "r!0d, r!1d, #!2d", 1),
+    ENCODING_MAP(THUMB_LSRV,          0x40c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "lsr", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_MOV_IMM,       0x2000, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mov", "r!0d, #!1d", 1),
+    ENCODING_MAP(THUMB_MOV_RR,        0x1c00, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mov", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_MOV_RR_H2H,    0x46c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mov", "r!0D, r!1D", 1),
+    ENCODING_MAP(THUMB_MOV_RR_H2L,    0x4640, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mov", "r!0d, r!1D", 1),
+    ENCODING_MAP(THUMB_MOV_RR_L2H,    0x4680, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mov", "r!0D, r!1d", 1),
+    ENCODING_MAP(THUMB_MUL,           0x4340, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mul", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_MVN,           0x43c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "mvn", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_NEG,           0x4240, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "neg", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_ORR,           0x4300, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "orr", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_POP,           0xbc00, 8, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP,
+                 "pop", "<!0R>", 1),
+    ENCODING_MAP(THUMB_PUSH,          0xb400, 8, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP,
+                 "push", "<!0R>", 1),
+    ENCODING_MAP(THUMB_ROR,           0x41c0, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "ror", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_SBC,           0x4180, 2, 0, 5, 3, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "sbc", "r!0d, r!1d", 1),
+    ENCODING_MAP(THUMB_STMIA,         0xc000, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_SRC1,
+                 "stmia", "r!0d!!, <!1R>", 1),
+    ENCODING_MAP(THUMB_STR_RRI5,      0x6000, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP,
+                 "str", "r!0d, [r!1d, #!2E]", 1),
+    ENCODING_MAP(THUMB_STR_RRR,       0x5000, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP,
+                 "str", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_STR_SP_REL,    0x9000, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP,
+                 "str", "r!0d, [sp, #!1E]", 1),
+    ENCODING_MAP(THUMB_STRB_RRI5,     0x7000, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP,
+                 "strb", "r!0d, [r!1d, #!2d]", 1),
+    ENCODING_MAP(THUMB_STRB_RRR,      0x5400, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP,
+                 "strb", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_STRH_RRI5,     0x8000, 2, 0, 5, 3, 10, 6,
+                 IS_TERTIARY_OP,
+                 "strh", "r!0d, [r!1d, #!2F]", 1),
+    ENCODING_MAP(THUMB_STRH_RRR,      0x5200, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP,
+                 "strh", "r!0d, [r!1d, r!2d]", 1),
+    ENCODING_MAP(THUMB_SUB_RRI3,      0x1e00, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "sub", "r!0d, r!1d, #!2d]", 1),
+    ENCODING_MAP(THUMB_SUB_RI8,       0x3800, 10, 8, 7, 0, -1, -1,
+                 IS_BINARY_OP | CLOBBER_DEST,
+                 "sub", "r!0d, #!1d", 1),
+    ENCODING_MAP(THUMB_SUB_RRR,       0x1a00, 2, 0, 5, 3, 8, 6,
+                 IS_TERTIARY_OP | CLOBBER_DEST,
+                 "sub", "r!0d, r!1d, r!2d", 1),
+    ENCODING_MAP(THUMB_SUB_SPI7,      0xb080, 6, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP | CLOBBER_DEST,
+                 "sub", "sp, #!0d", 1),
+    ENCODING_MAP(THUMB_SWI,           0xdf00, 7, 0, -1, -1, -1, -1,
+                 IS_UNARY_OP | IS_BRANCH,
+                 "swi", "!0d", 1),
+    ENCODING_MAP(THUMB_TST,           0x4200, 2, 0, 5, 3, -1, -1,
+                 IS_UNARY_OP,
+                 "tst", "r!0d, r!1d", 1),
+};
+
+#define PADDING_MOV_R0_R0               0x1C00
+
+/* Write the numbers in the literal pool to the codegen stream */
+static void installDataContent(CompilationUnit *cUnit)
+{
+    int *dataPtr = (int *) ((char *) cUnit->baseAddr + cUnit->dataOffset);
+    ArmLIR *dataLIR = (ArmLIR *) cUnit->wordList;
+    while (dataLIR) {
+        *dataPtr++ = dataLIR->operands[0];
+        dataLIR = NEXT_LIR(dataLIR);
+    }
+}
+
+/* Returns the size of a Jit trace description */
+static int jitTraceDescriptionSize(const JitTraceDescription *desc)
+{
+    int runCount;
+    for (runCount = 0; ; runCount++) {
+        if (desc->trace[runCount].frag.runEnd)
+           break;
+    }
+    return sizeof(JitCodeDesc) + ((runCount+1) * sizeof(JitTraceRun));
+}
+
+/* Return TRUE if error happens */
+static bool assembleInstructions(CompilationUnit *cUnit, intptr_t startAddr)
+{
+    short *bufferAddr = (short *) cUnit->codeBuffer;
+    ArmLIR *lir;
+
+    for (lir = (ArmLIR *) cUnit->firstLIRInsn; lir; lir = NEXT_LIR(lir)) {
+        if (lir->opCode < 0) {
+            if ((lir->opCode == ARM_PSEUDO_ALIGN4) &&
+                /* 1 means padding is needed */
+                (lir->operands[0] == 1)) {
+                *bufferAddr++ = PADDING_MOV_R0_R0;
+            }
+            continue;
+        }
+
+        if (lir->isNop) {
+            continue;
+        }
+
+        if (lir->opCode == THUMB_LDR_PC_REL ||
+            lir->opCode == THUMB_ADD_PC_REL) {
+            ArmLIR *lirTarget = (ArmLIR *) lir->generic.target;
+            intptr_t pc = (lir->generic.offset + 4) & ~3;
+            /*
+             * Allow an offset (stored in operands[2] to be added to the
+             * PC-relative target. Useful to get to a fixed field inside a
+             * chaining cell.
+             */
+            intptr_t target = lirTarget->generic.offset + lir->operands[2];
+            int delta = target - pc;
+            if (delta & 0x3) {
+                LOGE("PC-rel distance is not multiples of 4: %d\n", delta);
+                dvmAbort();
+            }
+            if (delta > 1023) {
+                return true;
+            }
+            lir->operands[1] = delta >> 2;
+        } else if (lir->opCode == THUMB_B_COND) {
+            ArmLIR *targetLIR = (ArmLIR *) lir->generic.target;
+            intptr_t pc = lir->generic.offset + 4;
+            intptr_t target = targetLIR->generic.offset;
+            int delta = target - pc;
+            if (delta > 254 || delta < -256) {
+                return true;
+            }
+            lir->operands[0] = delta >> 1;
+        } else if (lir->opCode == THUMB_B_UNCOND) {
+            ArmLIR *targetLIR = (ArmLIR *) lir->generic.target;
+            intptr_t pc = lir->generic.offset + 4;
+            intptr_t target = targetLIR->generic.offset;
+            int delta = target - pc;
+            if (delta > 2046 || delta < -2048) {
+                LOGE("Unconditional branch distance out of range: %d\n", delta);
+                dvmAbort();
+            }
+            lir->operands[0] = delta >> 1;
+        } else if (lir->opCode == THUMB_BLX_1) {
+            assert(NEXT_LIR(lir)->opCode == THUMB_BLX_2);
+            /* curPC is Thumb */
+            intptr_t curPC = (startAddr + lir->generic.offset + 4) & ~3;
+            intptr_t target = lir->operands[1];
+
+            /* Match bit[1] in target with base */
+            if (curPC & 0x2) {
+                target |= 0x2;
+            }
+            int delta = target - curPC;
+            assert((delta >= -(1<<22)) && (delta <= ((1<<22)-2)));
+
+            lir->operands[0] = (delta >> 12) & 0x7ff;
+            NEXT_LIR(lir)->operands[0] = (delta>> 1) & 0x7ff;
+        }
+
+        ArmEncodingMap *encoder = &EncodingMap[lir->opCode];
+        short bits = encoder->skeleton;
+        int i;
+        for (i = 0; i < 3; i++) {
+            short value;
+            if (encoder->fieldLoc[i].end != -1) {
+                value = (lir->operands[i] << encoder->fieldLoc[i].start) &
+                        ((1 << (encoder->fieldLoc[i].end + 1)) - 1);
+                bits |= value;
+
+            }
+        }
+        *bufferAddr++ = bits;
+    }
+    return false;
+}
+
+/*
+ * Translation layout in the code cache.  Note that the codeAddress pointer
+ * in JitTable will point directly to the code body (field codeAddress).  The
+ * chain cell offset codeAddress - 2, and (if present) executionCount is at
+ * codeAddress - 6.
+ *
+ *      +----------------------------+
+ *      | Execution count            |  -> [Optional] 4 bytes
+ *      +----------------------------+
+ *   +--| Offset to chain cell counts|  -> 2 bytes
+ *   |  +----------------------------+
+ *   |  | Code body                  |  -> Start address for translation
+ *   |  |                            |     variable in 2-byte chunks
+ *   |  .                            .     (JitTable's codeAddress points here)
+ *   |  .                            .
+ *   |  |                            |
+ *   |  +----------------------------+
+ *   |  | Chaining Cells             |  -> 8 bytes each, must be 4 byte aligned
+ *   |  .                            .
+ *   |  .                            .
+ *   |  |                            |
+ *   |  +----------------------------+
+ *   +->| Chaining cell counts       |  -> 4 bytes, chain cell counts by type
+ *      +----------------------------+
+ *      | Trace description          |  -> variable sized
+ *      .                            .
+ *      |                            |
+ *      +----------------------------+
+ *      | Literal pool               |  -> 4-byte aligned, variable size
+ *      .                            .
+ *      .                            .
+ *      |                            |
+ *      +----------------------------+
+ *
+ * Go over each instruction in the list and calculate the offset from the top
+ * before sending them off to the assembler. If out-of-range branch distance is
+ * seen rearrange the instructions a bit to correct it.
+ */
+void dvmCompilerAssembleLIR(CompilationUnit *cUnit, JitTranslationInfo *info)
+{
+    LIR *lir;
+    ArmLIR *armLIR;
+    int offset = 0;
+    int i;
+    ChainCellCounts chainCellCounts;
+    int descSize = jitTraceDescriptionSize(cUnit->traceDesc);
+
+    info->codeAddress = NULL;
+    info->instructionSet = cUnit->instructionSet;
+
+    /* Beginning offset needs to allow space for chain cell offset */
+    for (armLIR = (ArmLIR *) cUnit->firstLIRInsn;
+         armLIR;
+         armLIR = NEXT_LIR(armLIR)) {
+        armLIR->generic.offset = offset;
+        if (armLIR->opCode >= 0 && !armLIR->isNop) {
+            offset += 2;
+        } else if (armLIR->opCode == ARM_PSEUDO_ALIGN4) {
+            if (offset & 0x2) {
+                offset += 2;
+                armLIR->operands[0] = 1;
+            } else {
+                armLIR->operands[0] = 0;
+            }
+        }
+        /* Pseudo opcodes don't consume space */
+    }
+
+    /* Const values have to be word aligned */
+    offset = (offset + 3) & ~3;
+
+    /* Add space for chain cell counts & trace description */
+    u4 chainCellOffset = offset;
+    ArmLIR *chainCellOffsetLIR = (ArmLIR *) cUnit->chainCellOffsetLIR;
+    assert(chainCellOffsetLIR);
+    assert(chainCellOffset < 0x10000);
+    assert(chainCellOffsetLIR->opCode == ARM_16BIT_DATA &&
+           chainCellOffsetLIR->operands[0] == CHAIN_CELL_OFFSET_TAG);
+
+    /*
+     * Replace the CHAIN_CELL_OFFSET_TAG with the real value. If trace
+     * profiling is enabled, subtract 4 (occupied by the counter word) from
+     * the absolute offset as the value stored in chainCellOffsetLIR is the
+     * delta from &chainCellOffsetLIR to &ChainCellCounts.
+     */
+    chainCellOffsetLIR->operands[0] =
+        gDvmJit.profile ? (chainCellOffset - 4) : chainCellOffset;
+
+    offset += sizeof(chainCellCounts) + descSize;
+
+    assert((offset & 0x3) == 0);  /* Should still be word aligned */
+
+    /* Set up offsets for literals */
+    cUnit->dataOffset = offset;
+
+    for (lir = cUnit->wordList; lir; lir = lir->next) {
+        lir->offset = offset;
+        offset += 4;
+    }
+
+    cUnit->totalSize = offset;
+
+    if (gDvmJit.codeCacheByteUsed + cUnit->totalSize > CODE_CACHE_SIZE) {
+        gDvmJit.codeCacheFull = true;
+        cUnit->baseAddr = NULL;
+        return;
+    }
+
+    /* Allocate enough space for the code block */
+    cUnit->codeBuffer = dvmCompilerNew(chainCellOffset, true);
+    if (cUnit->codeBuffer == NULL) {
+        LOGE("Code buffer allocation failure\n");
+        cUnit->baseAddr = NULL;
+        return;
+    }
+
+    bool assemblerFailure = assembleInstructions(
+        cUnit, (intptr_t) gDvmJit.codeCache + gDvmJit.codeCacheByteUsed);
+
+    /*
+     * Currently the only reason that can cause the assembler to fail is due to
+     * trace length - cut it in half and retry.
+     */
+    if (assemblerFailure) {
+        cUnit->halveInstCount = true;
+        return;
+    }
+
+
+    cUnit->baseAddr = (char *) gDvmJit.codeCache + gDvmJit.codeCacheByteUsed;
+    gDvmJit.codeCacheByteUsed += offset;
+
+    /* Install the code block */
+    memcpy((char*)cUnit->baseAddr, cUnit->codeBuffer, chainCellOffset);
+    gDvmJit.numCompilations++;
+
+    /* Install the chaining cell counts */
+    for (i=0; i< CHAINING_CELL_LAST; i++) {
+        chainCellCounts.u.count[i] = cUnit->numChainingCells[i];
+    }
+    memcpy((char*)cUnit->baseAddr + chainCellOffset, &chainCellCounts,
+           sizeof(chainCellCounts));
+
+    /* Install the trace description */
+    memcpy((char*)cUnit->baseAddr + chainCellOffset + sizeof(chainCellCounts),
+           cUnit->traceDesc, descSize);
+
+    /* Write the literals directly into the code cache */
+    installDataContent(cUnit);
+
+    /* Flush dcache and invalidate the icache to maintain coherence */
+    cacheflush((long)cUnit->baseAddr,
+               (long)((char *) cUnit->baseAddr + offset), 0);
+
+    /* Record code entry point and instruction set */
+    info->codeAddress = (char*)cUnit->baseAddr + cUnit->headerSize;
+    info->instructionSet = cUnit->instructionSet;
+    /* If applicable, mark low bit to denote thumb */
+    if (info->instructionSet != DALVIK_JIT_ARM)
+        info->codeAddress = (char*)info->codeAddress + 1;
+}
+
+static u4 assembleBXPair(int branchOffset)
+{
+    u4 thumb1, thumb2;
+
+    if ((branchOffset < -2048) | (branchOffset > 2046)) {
+        thumb1 =  (0xf000 | ((branchOffset>>12) & 0x7ff));
+        thumb2 =  (0xf800 | ((branchOffset>> 1) & 0x7ff));
+    } else {
+        thumb1 =  (0xe000 | ((branchOffset>> 1) & 0x7ff));
+        thumb2 =  0x4300;  /* nop -> or r0, r0 */
+    }
+
+    return thumb2<<16 | thumb1;
+}
+
+/*
+ * Perform translation chain operation.
+ * For ARM, we'll use a pair of thumb instructions to generate
+ * an unconditional chaining branch of up to 4MB in distance.
+ * Use a BL, though we don't really need the link.  The format is
+ *     111HHooooooooooo
+ * Where HH is 10 for the 1st inst, and 11 for the second and
+ * the "o" field is each instruction's 11-bit contribution to the
+ * 22-bit branch offset.
+ * If the target is nearby, use a single-instruction bl.
+ * If one or more threads is suspended, don't chain.
+ */
+void* dvmJitChain(void* tgtAddr, u4* branchAddr)
+{
+    int baseAddr = (u4) branchAddr + 4;
+    int branchOffset = (int) tgtAddr - baseAddr;
+    u4 newInst;
+
+    if (gDvm.sumThreadSuspendCount == 0) {
+        assert((branchOffset >= -(1<<22)) && (branchOffset <= ((1<<22)-2)));
+
+        gDvmJit.translationChains++;
+
+        COMPILER_TRACE_CHAINING(
+            LOGD("Jit Runtime: chaining 0x%x to 0x%x\n",
+                 (int) branchAddr, (int) tgtAddr & -2));
+
+        newInst = assembleBXPair(branchOffset);
+
+        *branchAddr = newInst;
+        cacheflush((long)branchAddr, (long)branchAddr + 4, 0);
+    }
+
+    return tgtAddr;
+}
+
+/*
+ * This method is called from the invoke templates for virtual and interface
+ * methods to speculatively setup a chain to the callee. The templates are
+ * written in assembly and have setup method, cell, and clazz at r0, r2, and
+ * r3 respectively, so there is a unused argument in the list. Upon return one
+ * of the following three results may happen:
+ *   1) Chain is not setup because the callee is native. Reset the rechain
+ *      count to a big number so that it will take a long time before the next
+ *      rechain attempt to happen.
+ *   2) Chain is not setup because the callee has not been created yet. Reset
+ *      the rechain count to a small number and retry in the near future.
+ *   3) Ask all other threads to stop before patching this chaining cell.
+ *      This is required because another thread may have passed the class check
+ *      but hasn't reached the chaining cell yet to follow the chain. If we
+ *      patch the content before halting the other thread, there could be a
+ *      small window for race conditions to happen that it may follow the new
+ *      but wrong chain to invoke a different method.
+ */
+const Method *dvmJitToPatchPredictedChain(const Method *method,
+                                          void *unused,
+                                          PredictedChainingCell *cell,
+                                          const ClassObject *clazz)
+{
+    /* Don't come back here for a long time if the method is native */
+    if (dvmIsNativeMethod(method)) {
+        cell->counter = PREDICTED_CHAIN_COUNTER_AVOID;
+        cacheflush((long) cell, (long) (cell+1), 0);
+        COMPILER_TRACE_CHAINING(
+            LOGD("Jit Runtime: predicted chain %p to native method %s ignored",
+                 cell, method->name));
+        goto done;
+    }
+    int tgtAddr = (int) dvmJitGetCodeAddr(method->insns);
+
+    /*
+     * Compilation not made yet for the callee. Reset the counter to a small
+     * value and come back to check soon.
+     */
+    if (tgtAddr == 0) {
+        /*
+         * Wait for a few invocations (currently set to be 16) before trying
+         * to setup the chain again.
+         */
+        cell->counter = PREDICTED_CHAIN_COUNTER_DELAY;
+        cacheflush((long) cell, (long) (cell+1), 0);
+        COMPILER_TRACE_CHAINING(
+            LOGD("Jit Runtime: predicted chain %p to method %s delayed",
+                 cell, method->name));
+        goto done;
+    }
+
+    /* Stop the world */
+    dvmSuspendAllThreads(SUSPEND_FOR_JIT);
+
+    int baseAddr = (int) cell + 4;   // PC is cur_addr + 4
+    int branchOffset = tgtAddr - baseAddr;
+
+    COMPILER_TRACE_CHAINING(
+        LOGD("Jit Runtime: predicted chain %p from %s to %s (%s) patched",
+             cell, cell->clazz ? cell->clazz->descriptor : "NULL",
+             clazz->descriptor,
+             method->name));
+
+    cell->branch = assembleBXPair(branchOffset);
+    cell->clazz = clazz;
+    cell->method = method;
+    cell->counter = PREDICTED_CHAIN_COUNTER_RECHAIN;
+
+    cacheflush((long) cell, (long) (cell+1), 0);
+
+    /* All done - resume all other threads */
+    dvmResumeAllThreads(SUSPEND_FOR_JIT);
+
+done:
+    return method;
+}
+
+/*
+ * Unchain a trace given the starting address of the translation
+ * in the code cache.  Refer to the diagram in dvmCompilerAssembleLIR.
+ * Returns the address following the last cell unchained.  Note that
+ * the incoming codeAddr is a thumb code address, and therefore has
+ * the low bit set.
+ */
+u4* dvmJitUnchain(void* codeAddr)
+{
+    u2* pChainCellOffset = (u2*)((char*)codeAddr - 3);
+    u2 chainCellOffset = *pChainCellOffset;
+    ChainCellCounts *pChainCellCounts =
+          (ChainCellCounts*)((char*)codeAddr + chainCellOffset - 3);
+    int cellSize;
+    u4* pChainCells;
+    u4* pStart;
+    u4 thumb1;
+    u4 thumb2;
+    u4 newInst;
+    int i,j;
+    PredictedChainingCell *predChainCell;
+
+    /* Get total count of chain cells */
+    for (i = 0, cellSize = 0; i < CHAINING_CELL_LAST; i++) {
+        if (i != CHAINING_CELL_INVOKE_PREDICTED) {
+            cellSize += pChainCellCounts->u.count[i] * 2;
+        } else {
+            cellSize += pChainCellCounts->u.count[i] * 4;
+        }
+    }
+
+    /* Locate the beginning of the chain cell region */
+    pStart = pChainCells = ((u4 *) pChainCellCounts) - cellSize;
+
+    /* The cells are sorted in order - walk through them and reset */
+    for (i = 0; i < CHAINING_CELL_LAST; i++) {
+        int elemSize = 2; /* Most chaining cell has two words */
+        if (i == CHAINING_CELL_INVOKE_PREDICTED) {
+            elemSize = 4;
+        }
+
+        for (j = 0; j < pChainCellCounts->u.count[i]; j++) {
+            int targetOffset;
+            switch(i) {
+                case CHAINING_CELL_NORMAL:
+                    targetOffset = offsetof(InterpState,
+                          jitToInterpEntries.dvmJitToInterpNormal);
+                    break;
+                case CHAINING_CELL_HOT:
+                case CHAINING_CELL_INVOKE_SINGLETON:
+                    targetOffset = offsetof(InterpState,
+                          jitToInterpEntries.dvmJitToTraceSelect);
+                    break;
+                case CHAINING_CELL_INVOKE_PREDICTED:
+                    targetOffset = 0;
+                    predChainCell = (PredictedChainingCell *) pChainCells;
+                    /* Reset the cell to the init state */
+                    predChainCell->branch = PREDICTED_CHAIN_BX_PAIR_INIT;
+                    predChainCell->clazz = PREDICTED_CHAIN_CLAZZ_INIT;
+                    predChainCell->method = PREDICTED_CHAIN_METHOD_INIT;
+                    predChainCell->counter = PREDICTED_CHAIN_COUNTER_INIT;
+                    break;
+                default:
+                    dvmAbort();
+            }
+            COMPILER_TRACE_CHAINING(
+                LOGD("Jit Runtime: unchaining 0x%x", (int)pChainCells));
+            /*
+             * Thumb code sequence for a chaining cell is:
+             *     ldr  r0, rGLUE, #<word offset>
+             *     blx  r0
+             */
+            if (i != CHAINING_CELL_INVOKE_PREDICTED) {
+                targetOffset = targetOffset >> 2;  /* convert to word offset */
+                thumb1 = 0x6800 | (targetOffset << 6) |
+                         (rGLUE << 3) | (r0 << 0);
+                thumb2 = 0x4780 | (r0 << 3);
+                newInst = thumb2<<16 | thumb1;
+                *pChainCells = newInst;
+            }
+            pChainCells += elemSize;  /* Advance by a fixed number of words */
+        }
+    }
+    return pChainCells;
+}
+
+/* Unchain all translation in the cache. */
+void dvmJitUnchainAll()
+{
+    u4* lowAddress = NULL;
+    u4* highAddress = NULL;
+    unsigned int i;
+    if (gDvmJit.pJitEntryTable != NULL) {
+        COMPILER_TRACE_CHAINING(LOGD("Jit Runtime: unchaining all"));
+        dvmLockMutex(&gDvmJit.tableLock);
+        for (i = 0; i < gDvmJit.jitTableSize; i++) {
+            if (gDvmJit.pJitEntryTable[i].dPC &&
+                   gDvmJit.pJitEntryTable[i].codeAddress) {
+                u4* lastAddress;
+                lastAddress =
+                      dvmJitUnchain(gDvmJit.pJitEntryTable[i].codeAddress);
+                if (lowAddress == NULL ||
+                      (u4*)gDvmJit.pJitEntryTable[i].codeAddress < lowAddress)
+                    lowAddress = lastAddress;
+                if (lastAddress > highAddress)
+                    highAddress = lastAddress;
+            }
+        }
+        cacheflush((long)lowAddress, (long)highAddress, 0);
+        dvmUnlockMutex(&gDvmJit.tableLock);
+    }
+}
+
+typedef struct jitProfileAddrToLine {
+    u4 lineNum;
+    u4 bytecodeOffset;
+} jitProfileAddrToLine;
+
+
+/* Callback function to track the bytecode offset/line number relationiship */
+static int addrToLineCb (void *cnxt, u4 bytecodeOffset, u4 lineNum)
+{
+    jitProfileAddrToLine *addrToLine = (jitProfileAddrToLine *) cnxt;
+
+    /* Best match so far for this offset */
+    if (addrToLine->bytecodeOffset >= bytecodeOffset) {
+        addrToLine->lineNum = lineNum;
+    }
+    return 0;
+}
+
+char *getTraceBase(const JitEntry *p)
+{
+    return (char*)p->codeAddress -
+        (6 + (p->u.info.instructionSet == DALVIK_JIT_ARM ? 0 : 1));
+}
+
+/* Dumps profile info for a single trace */
+static int dumpTraceProfile(JitEntry *p)
+{
+    ChainCellCounts* pCellCounts;
+    char* traceBase;
+    u4* pExecutionCount;
+    u2* pCellOffset;
+    JitTraceDescription *desc;
+    const Method* method;
+
+    traceBase = getTraceBase(p);
+
+    if (p->codeAddress == NULL) {
+        LOGD("TRACEPROFILE 0x%08x 0 NULL 0 0", (int)traceBase);
+        return 0;
+    }
+
+    pExecutionCount = (u4*) (traceBase);
+    pCellOffset = (u2*) (traceBase + 4);
+    pCellCounts = (ChainCellCounts*) ((char *)pCellOffset + *pCellOffset);
+    desc = (JitTraceDescription*) ((char*)pCellCounts + sizeof(*pCellCounts));
+    method = desc->method;
+    char *methodDesc = dexProtoCopyMethodDescriptor(&method->prototype);
+    jitProfileAddrToLine addrToLine = {0, desc->trace[0].frag.startOffset};
+
+    /*
+     * We may end up decoding the debug information for the same method
+     * multiple times, but the tradeoff is we don't need to allocate extra
+     * space to store the addr/line mapping. Since this is a debugging feature
+     * and done infrequently so the slower but simpler mechanism should work
+     * just fine.
+     */
+    dexDecodeDebugInfo(method->clazz->pDvmDex->pDexFile,
+                       dvmGetMethodCode(method),
+                       method->clazz->descriptor,
+                       method->prototype.protoIdx,
+                       method->accessFlags,
+                       addrToLineCb, NULL, &addrToLine);
+
+    LOGD("TRACEPROFILE 0x%08x % 10d [%#x(+%d), %d] %s%s;%s",
+         (int)traceBase,
+         *pExecutionCount,
+         desc->trace[0].frag.startOffset,
+         desc->trace[0].frag.numInsts,
+         addrToLine.lineNum,
+         method->clazz->descriptor, method->name, methodDesc);
+    free(methodDesc);
+
+    return *pExecutionCount;
+}
+
+/* Handy function to retrieve the profile count */
+static inline int getProfileCount(const JitEntry *entry)
+{
+    if (entry->dPC == 0 || entry->codeAddress == 0)
+        return 0;
+    u4 *pExecutionCount = (u4 *) getTraceBase(entry);
+
+    return *pExecutionCount;
+}
+
+
+/* qsort callback function */
+static int sortTraceProfileCount(const void *entry1, const void *entry2)
+{
+    const JitEntry *jitEntry1 = entry1;
+    const JitEntry *jitEntry2 = entry2;
+
+    int count1 = getProfileCount(jitEntry1);
+    int count2 = getProfileCount(jitEntry2);
+    return (count1 == count2) ? 0 : ((count1 > count2) ? -1 : 1);
+}
+
+/* Sort the trace profile counts and dump them */
+void dvmCompilerSortAndPrintTraceProfiles()
+{
+    JitEntry *sortedEntries;
+    int numTraces = 0;
+    unsigned long counts = 0;
+    unsigned int i;
+
+    /* Make sure that the table is not changing */
+    dvmLockMutex(&gDvmJit.tableLock);
+
+    /* Sort the entries by descending order */
+    sortedEntries = malloc(sizeof(JitEntry) * gDvmJit.jitTableSize);
+    if (sortedEntries == NULL)
+        goto done;
+    memcpy(sortedEntries, gDvmJit.pJitEntryTable,
+           sizeof(JitEntry) * gDvmJit.jitTableSize);
+    qsort(sortedEntries, gDvmJit.jitTableSize, sizeof(JitEntry),
+          sortTraceProfileCount);
+
+    /* Dump the sorted entries */
+    for (i=0; i < gDvmJit.jitTableSize; i++) {
+        if (sortedEntries[i].dPC != 0) {
+            counts += dumpTraceProfile(&sortedEntries[i]);
+            numTraces++;
+        }
+    }
+    if (numTraces == 0)
+        numTraces = 1;
+    LOGD("JIT: Average execution count -> %d",(int)(counts / numTraces));
+
+    free(sortedEntries);
+done:
+    dvmUnlockMutex(&gDvmJit.tableLock);
+    return;
+}