JIT: Support for shift field in disassembler [issue 2465170]

Many Thumb2 instructions allow for an optional shift to be applied to
operand 2.  This cl enhances the disassembler to show a non-zero shift
in the dump output.

Change-Id: I6cbfec46cd45e3f2acc9553f880e80764a1eb65d

2 files changed, 23 insertions, 8 deletions

diff --git a/vm/compiler/codegen/arm/ArchUtility.c b/vm/compiler/codegen/arm/ArchUtility.c
index d5acd13ef..2e6845968 100644
--- a/vm/compiler/codegen/arm/ArchUtility.c
+++ b/vm/compiler/codegen/arm/ArchUtility.c
@@ -18,6 +18,12 @@
 #include "libdex/OpCodeNames.h"
 #include "ArmLIR.h"
 
+static char *shiftNames[4] = {
+    "lsl",
+    "lsr",
+    "asr",
+    "ror"};
+
 /* Decode and print a ARM register name */
 static char * decodeRegList(int vector, char *buf)
 {
@@ -83,6 +89,14 @@ static void buildInsnString(char *fmt, ArmLIR *lir, char* buf,
                assert((unsigned)(nc-'0') < 4);
                operand = lir->operands[nc-'0'];
                switch(*fmt++) {
+                   case 'H':
+                       if (operand != 0) {
+                           sprintf(tbuf, ", %s %d",shiftNames[operand & 0x3],
+                                   operand >> 2);
+                       } else {
+                           strcpy(tbuf,"");
+                       }
+                       break;
                    case 'B':
                        switch (operand) {
                            case kSY:
diff --git a/vm/compiler/codegen/arm/Assemble.c b/vm/compiler/codegen/arm/Assemble.c
index 4f975b363..5f54ebe0d 100644
--- a/vm/compiler/codegen/arm/Assemble.c
+++ b/vm/compiler/codegen/arm/Assemble.c
@@ -74,6 +74,7 @@
  *     M -> Thumb2 16-bit zero-extended immediate
  *     b -> 4-digit binary
  *     B -> dmb option string (sy, st, ish, ishst, nsh, hshst)
+ *     H -> operand shift
  *
  *  [!] escape.  To insert "!", use "!!"
  */
@@ -543,17 +544,17 @@ ArmEncodingMap EncodingMap[kArmLast] = {
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1,
                  IS_QUAD_OP | REG_DEF0_USE12 | SETS_CCODES,
-                 "adds", "r!0d, r!1d, r!2d", 2),
+                 "adds", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2SubRRR,       0xebb00000, /* setflags enconding */
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1,
                  IS_QUAD_OP | REG_DEF0_USE12 | SETS_CCODES,
-                 "subs", "r!0d, r!1d, r!2d", 2),
+                 "subs", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2SbcRRR,       0xeb700000, /* setflags encoding */
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1,
                  IS_QUAD_OP | REG_DEF0_USE12 | USES_CCODES | SETS_CCODES,
-                 "sbcs", "r!0d, r!1d, r!2d", 2),
+                 "sbcs", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2CmpRR,       0xebb00f00,
                  kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0, kFmtShift, -1, -1,
                  kFmtUnused, -1, -1,
@@ -656,15 +657,15 @@ ArmEncodingMap EncodingMap[kArmLast] = {
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1,
                  IS_QUAD_OP | REG_DEF0_USE12 | SETS_CCODES,
-                 "adcs", "r!0d, r!1d, r!2d, shift !3d", 2),
+                 "adcs", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2AndRRR,  0xea000000,
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1, IS_QUAD_OP | REG_DEF0_USE12,
-                 "and", "r!0d, r!1d, r!2d, shift !3d", 2),
+                 "and", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2BicRRR,  0xea200000,
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1, IS_QUAD_OP | REG_DEF0_USE12,
-                 "bic", "r!0d, r!1d, r!2d, shift !3d", 2),
+                 "bic", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2CmnRR,  0xeb000000,
                  kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0, kFmtShift, -1, -1,
                  kFmtUnused, -1, -1,
@@ -673,7 +674,7 @@ ArmEncodingMap EncodingMap[kArmLast] = {
     ENCODING_MAP(kThumb2EorRRR,  0xea800000,
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1, IS_QUAD_OP | REG_DEF0_USE12,
-                 "eor", "r!0d, r!1d, r!2d, shift !3d", 2),
+                 "eor", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2MulRRR,  0xfb00f000,
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtUnused, -1, -1, IS_TERTIARY_OP | REG_DEF0_USE12,
@@ -695,7 +696,7 @@ ArmEncodingMap EncodingMap[kArmLast] = {
     ENCODING_MAP(kThumb2OrrRRR,  0xea400000,
                  kFmtBitBlt, 11, 8, kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0,
                  kFmtShift, -1, -1, IS_QUAD_OP | REG_DEF0_USE12,
-                 "orr", "r!0d, r!1d, r!2d, shift !3d", 2),
+                 "orr", "r!0d, r!1d, r!2d!3H", 2),
     ENCODING_MAP(kThumb2TstRR,       0xea100f00,
                  kFmtBitBlt, 19, 16, kFmtBitBlt, 3, 0, kFmtShift, -1, -1,
                  kFmtUnused, -1, -1,