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

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

Change-Id: I5cd4c6d86f0f6a966c059715b98db35cc8f9de76

4 files changed, 139 insertions, 18 deletions

diff --git a/compiler/optimizing/builder.cc b/compiler/optimizing/builder.cc
index df3d57ebdf..b51b6e7d25 100644
--- a/compiler/optimizing/builder.cc
+++ b/compiler/optimizing/builder.cc
@@ -1007,6 +1007,11 @@ bool HGraphBuilder::AnalyzeDexInstruction(const Instruction& instruction, uint32
       break;
     }
 
+    case Instruction::INT_TO_CHAR: {
+      Conversion_12x(instruction, Primitive::kPrimInt, Primitive::kPrimChar);
+      break;
+    }
+
     case Instruction::ADD_INT: {
       Binop_23x<HAdd>(instruction, Primitive::kPrimInt);
       break;
diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc
index 7444506771..09e1b97570 100644
--- a/compiler/optimizing/code_generator_arm.cc
+++ b/compiler/optimizing/code_generator_arm.cc
@@ -1356,7 +1356,7 @@ void LocationsBuilderARM::VisitTypeConversion(HTypeConversion* conversion) {
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-byte conversion.
+          // Processing a Dex `int-to-byte' instruction.
           locations->SetInAt(0, Location::RequiresRegister());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1370,7 +1370,7 @@ void LocationsBuilderARM::VisitTypeConversion(HTypeConversion* conversion) {
     case Primitive::kPrimInt:
       switch (input_type) {
         case Primitive::kPrimLong:
-          // long-to-int conversion.
+          // Processing a Dex `long-to-int' instruction.
           locations->SetInAt(0, Location::Any());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1393,7 +1393,7 @@ void LocationsBuilderARM::VisitTypeConversion(HTypeConversion* conversion) {
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-long conversion.
+          // Processing a Dex `int-to-long' instruction.
           locations->SetInAt(0, Location::RequiresRegister());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1410,6 +1410,23 @@ void LocationsBuilderARM::VisitTypeConversion(HTypeConversion* conversion) {
       }
       break;
 
+    case Primitive::kPrimChar:
+      switch (input_type) {
+        case Primitive::kPrimByte:
+        case Primitive::kPrimShort:
+        case Primitive::kPrimInt:
+        case Primitive::kPrimChar:
+          // Processing a Dex `int-to-char' instruction.
+          locations->SetInAt(0, Location::RequiresRegister());
+          locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
+          break;
+
+        default:
+          LOG(FATAL) << "Unexpected type conversion from " << input_type
+                     << " to " << result_type;
+      }
+      break;
+
     case Primitive::kPrimFloat:
     case Primitive::kPrimDouble:
       LOG(FATAL) << "Type conversion from " << input_type
@@ -1434,7 +1451,7 @@ void InstructionCodeGeneratorARM::VisitTypeConversion(HTypeConversion* conversio
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-byte conversion.
+          // Processing a Dex `int-to-byte' instruction.
           __ sbfx(out.As<Register>(), in.As<Register>(), 0, 8);
           break;
 
@@ -1447,7 +1464,7 @@ void InstructionCodeGeneratorARM::VisitTypeConversion(HTypeConversion* conversio
     case Primitive::kPrimInt:
       switch (input_type) {
         case Primitive::kPrimLong:
-          // long-to-int conversion.
+          // Processing a Dex `long-to-int' instruction.
           DCHECK(out.IsRegister());
           if (in.IsRegisterPair()) {
             __ Mov(out.As<Register>(), in.AsRegisterPairLow<Register>());
@@ -1479,7 +1496,7 @@ void InstructionCodeGeneratorARM::VisitTypeConversion(HTypeConversion* conversio
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-long conversion.
+          // Processing a Dex `int-to-long' instruction.
           DCHECK(out.IsRegisterPair());
           DCHECK(in.IsRegister());
           __ Mov(out.AsRegisterPairLow<Register>(), in.As<Register>());
@@ -1501,6 +1518,22 @@ void InstructionCodeGeneratorARM::VisitTypeConversion(HTypeConversion* conversio
       }
       break;
 
+    case Primitive::kPrimChar:
+      switch (input_type) {
+        case Primitive::kPrimByte:
+        case Primitive::kPrimShort:
+        case Primitive::kPrimInt:
+        case Primitive::kPrimChar:
+          // Processing a Dex `int-to-char' instruction.
+          __ ubfx(out.As<Register>(), in.As<Register>(), 0, 16);
+          break;
+
+        default:
+          LOG(FATAL) << "Unexpected type conversion from " << input_type
+                     << " to " << result_type;
+      }
+      break;
+
     case Primitive::kPrimFloat:
     case Primitive::kPrimDouble:
       LOG(FATAL) << "Type conversion from " << input_type
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 6e1abbf076..8a8fec2609 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -1295,7 +1295,7 @@ void LocationsBuilderX86::VisitTypeConversion(HTypeConversion* conversion) {
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-byte conversion.
+          // Processing a Dex `int-to-byte' instruction.
           locations->SetInAt(0, Location::Any());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1309,7 +1309,7 @@ void LocationsBuilderX86::VisitTypeConversion(HTypeConversion* conversion) {
     case Primitive::kPrimInt:
       switch (input_type) {
         case Primitive::kPrimLong:
-          // long-to-int conversion.
+          // Processing a Dex `long-to-int' instruction.
           locations->SetInAt(0, Location::Any());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1332,7 +1332,7 @@ void LocationsBuilderX86::VisitTypeConversion(HTypeConversion* conversion) {
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-long conversion.
+          // Processing a Dex `int-to-long' instruction.
           locations->SetInAt(0, Location::RegisterLocation(EAX));
           locations->SetOut(Location::RegisterPairLocation(EAX, EDX));
           break;
@@ -1349,6 +1349,23 @@ void LocationsBuilderX86::VisitTypeConversion(HTypeConversion* conversion) {
       }
       break;
 
+    case Primitive::kPrimChar:
+      switch (input_type) {
+        case Primitive::kPrimByte:
+        case Primitive::kPrimShort:
+        case Primitive::kPrimInt:
+        case Primitive::kPrimChar:
+          // Processing a Dex `int-to-char' instruction.
+          locations->SetInAt(0, Location::Any());
+          locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
+          break;
+
+        default:
+          LOG(FATAL) << "Unexpected type conversion from " << input_type
+                     << " to " << result_type;
+      }
+      break;
+
     case Primitive::kPrimFloat:
     case Primitive::kPrimDouble:
       LOG(FATAL) << "Type conversion from " << input_type
@@ -1373,7 +1390,7 @@ void InstructionCodeGeneratorX86::VisitTypeConversion(HTypeConversion* conversio
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-byte conversion.
+          // Processing a Dex `int-to-byte' instruction.
           if (in.IsRegister()) {
             __ movsxb(out.As<Register>(), in.As<ByteRegister>());
           } else if (in.IsStackSlot()) {
@@ -1394,7 +1411,7 @@ void InstructionCodeGeneratorX86::VisitTypeConversion(HTypeConversion* conversio
     case Primitive::kPrimInt:
       switch (input_type) {
         case Primitive::kPrimLong:
-          // long-to-int conversion.
+          // Processing a Dex `long-to-int' instruction.
           if (in.IsRegisterPair()) {
             __ movl(out.As<Register>(), in.AsRegisterPairLow<Register>());
           } else if (in.IsDoubleStackSlot()) {
@@ -1425,7 +1442,7 @@ void InstructionCodeGeneratorX86::VisitTypeConversion(HTypeConversion* conversio
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-long conversion.
+          // Processing a Dex `int-to-long' instruction.
           DCHECK_EQ(out.AsRegisterPairLow<Register>(), EAX);
           DCHECK_EQ(out.AsRegisterPairHigh<Register>(), EDX);
           DCHECK_EQ(in.As<Register>(), EAX);
@@ -1444,6 +1461,30 @@ void InstructionCodeGeneratorX86::VisitTypeConversion(HTypeConversion* conversio
       }
       break;
 
+    case Primitive::kPrimChar:
+      switch (input_type) {
+        case Primitive::kPrimByte:
+        case Primitive::kPrimShort:
+        case Primitive::kPrimInt:
+        case Primitive::kPrimChar:
+          // Processing a Dex `Process a Dex `int-to-char'' instruction.
+          if (in.IsRegister()) {
+            __ movzxw(out.As<Register>(), in.As<Register>());
+          } else if (in.IsStackSlot()) {
+            __ movzxw(out.As<Register>(), Address(ESP, in.GetStackIndex()));
+          } else {
+            DCHECK(in.GetConstant()->IsIntConstant());
+            int32_t value = in.GetConstant()->AsIntConstant()->GetValue();
+            __ movl(out.As<Register>(), Immediate(static_cast<uint16_t>(value)));
+          }
+          break;
+
+        default:
+          LOG(FATAL) << "Unexpected type conversion from " << input_type
+                     << " to " << result_type;
+      }
+      break;
+
     case Primitive::kPrimFloat:
     case Primitive::kPrimDouble:
       LOG(FATAL) << "Type conversion from " << input_type
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index 2393fb5119..5aa1c4a6c8 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -1293,7 +1293,7 @@ void LocationsBuilderX86_64::VisitTypeConversion(HTypeConversion* conversion) {
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-byte conversion.
+          // Processing a Dex `int-to-byte' instruction.
           locations->SetInAt(0, Location::Any());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1307,7 +1307,7 @@ void LocationsBuilderX86_64::VisitTypeConversion(HTypeConversion* conversion) {
     case Primitive::kPrimInt:
       switch (input_type) {
         case Primitive::kPrimLong:
-          // long-to-int conversion.
+          // Processing a Dex `long-to-int' instruction.
           locations->SetInAt(0, Location::Any());
           locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
           break;
@@ -1330,7 +1330,7 @@ void LocationsBuilderX86_64::VisitTypeConversion(HTypeConversion* conversion) {
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-long conversion.
+          // Processing a Dex `int-to-long' instruction.
           // TODO: We would benefit from a (to-be-implemented)
           // Location::RegisterOrStackSlot requirement for this input.
           locations->SetInAt(0, Location::RequiresRegister());
@@ -1349,6 +1349,23 @@ void LocationsBuilderX86_64::VisitTypeConversion(HTypeConversion* conversion) {
       }
       break;
 
+    case Primitive::kPrimChar:
+      switch (input_type) {
+        case Primitive::kPrimByte:
+        case Primitive::kPrimShort:
+        case Primitive::kPrimInt:
+        case Primitive::kPrimChar:
+          // Processing a Dex `int-to-char' instruction.
+          locations->SetInAt(0, Location::Any());
+          locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
+          break;
+
+        default:
+          LOG(FATAL) << "Unexpected type conversion from " << input_type
+                     << " to " << result_type;
+      }
+      break;
+
     case Primitive::kPrimFloat:
     case Primitive::kPrimDouble:
       LOG(FATAL) << "Type conversion from " << input_type
@@ -1373,7 +1390,7 @@ void InstructionCodeGeneratorX86_64::VisitTypeConversion(HTypeConversion* conver
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-byte conversion.
+          // Processing a Dex `int-to-byte' instruction.
           if (in.IsRegister()) {
             __ movsxb(out.As<CpuRegister>(), in.As<CpuRegister>());
           } else if (in.IsStackSlot()) {
@@ -1395,7 +1412,7 @@ void InstructionCodeGeneratorX86_64::VisitTypeConversion(HTypeConversion* conver
     case Primitive::kPrimInt:
       switch (input_type) {
         case Primitive::kPrimLong:
-          // long-to-int conversion.
+          // Processing a Dex `long-to-int' instruction.
           if (in.IsRegister()) {
             __ movl(out.As<CpuRegister>(), in.As<CpuRegister>());
           } else if (in.IsDoubleStackSlot()) {
@@ -1428,7 +1445,7 @@ void InstructionCodeGeneratorX86_64::VisitTypeConversion(HTypeConversion* conver
         case Primitive::kPrimShort:
         case Primitive::kPrimInt:
         case Primitive::kPrimChar:
-          // int-to-long conversion.
+          // Processing a Dex `int-to-long' instruction.
           DCHECK(in.IsRegister());
           __ movsxd(out.As<CpuRegister>(), in.As<CpuRegister>());
           break;
@@ -1445,6 +1462,31 @@ void InstructionCodeGeneratorX86_64::VisitTypeConversion(HTypeConversion* conver
       }
       break;
 
+    case Primitive::kPrimChar:
+      switch (input_type) {
+        case Primitive::kPrimByte:
+        case Primitive::kPrimShort:
+        case Primitive::kPrimInt:
+        case Primitive::kPrimChar:
+          // Processing a Dex `int-to-char' instruction.
+          if (in.IsRegister()) {
+            __ movzxw(out.As<CpuRegister>(), in.As<CpuRegister>());
+          } else if (in.IsStackSlot()) {
+            __ movzxw(out.As<CpuRegister>(),
+                      Address(CpuRegister(RSP), in.GetStackIndex()));
+          } else {
+            DCHECK(in.GetConstant()->IsIntConstant());
+            __ movl(out.As<CpuRegister>(),
+                    Immediate(static_cast<uint16_t>(in.GetConstant()->AsIntConstant()->GetValue())));
+          }
+          break;
+
+        default:
+          LOG(FATAL) << "Unexpected type conversion from " << input_type
+                     << " to " << result_type;
+      }
+      break;
+
     case Primitive::kPrimFloat:
     case Primitive::kPrimDouble:
       LOG(FATAL) << "Type conversion from " << input_type