Add support for int-to-byte in the optimizing compiler.

- Add support for the int-to-byte Dex instruction in the
  optimizing compiler.
- Implement the ARM and Thumb-2 SBFX instructions.
- Generate x86, x86-64 and ARM (but not ARM64) code for
  char to byte, short to byte and int to byte
  HTypeConversion nodes.
- Add related tests to test/422-type-conversion.

Change-Id: Ic8b8911b90d4b5281fad15bcee96bc3ee85dc577
diff --git a/compiler/utils/arm/assembler_arm32.cc b/compiler/utils/arm/assembler_arm32.cc
index c8a57b1..29cbf58 100644
--- a/compiler/utils/arm/assembler_arm32.cc
+++ b/compiler/utils/arm/assembler_arm32.cc
@@ -208,6 +208,25 @@
 }
 
 
+void Arm32Assembler::sbfx(Register rd, Register rn, uint32_t lsb, uint32_t width, Condition cond) {
+  CHECK_NE(rd, kNoRegister);
+  CHECK_NE(rn, kNoRegister);
+  CHECK_NE(cond, kNoCondition);
+  CHECK_LE(lsb, 31U);
+  CHECK(1U <= width && width <= 32U) << width;
+  uint32_t widthminus1 = width - 1;
+
+  int32_t encoding = (static_cast<int32_t>(cond) << kConditionShift) |
+      B26 | B25 | B24 | B23 | B21 |
+      (widthminus1 << 16) |
+      (static_cast<uint32_t>(rd) << 12) |
+      (lsb << 7) |
+      B6 | B4 |
+      static_cast<uint32_t>(rn);
+  Emit(encoding);
+}
+
+
 void Arm32Assembler::ldr(Register rd, const Address& ad, Condition cond) {
   EmitMemOp(cond, true, false, rd, ad);
 }