Range feedback for binary integer operations.

runtime/vm/assembler_arm.cc

Index: runtime/vm/assembler_arm.cc
diff --git a/runtime/vm/assembler_arm.cc b/runtime/vm/assembler_arm.cc
index 1fe7e91c178d8ba8c1663522b685033dba36c548..1b1b68faca02ed03605186015f3083704a88322c 100644
--- a/runtime/vm/assembler_arm.cc
+++ b/runtime/vm/assembler_arm.cc
@@ -1934,6 +1934,46 @@ void Assembler::LoadTaggedClassIdMayBeSmi(Register result, Register object) {
 }
 
 
+void Assembler::ComputeRange(Register result,
+                             Register value,
+                             Register scratch,
+                             Label* not_mint) {
+  const Register hi = TMP;
+  const Register lo = scratch;
+
+  Label done;
+  mov(result, Operand(value, LSR, kBitsPerWord - 1));
+  tst(value, Operand(kSmiTagMask));
+  b(&done, EQ);
+  CompareClassId(value, kMintCid, result);
+  b(not_mint, NE);
+  ldr(hi, FieldAddress(value, Mint::value_offset() + kWordSize));
+  ldr(lo, FieldAddress(value, Mint::value_offset()));
+  rsb(result, hi, Operand(ICData::kInt32Bit));
+  cmp(hi, Operand(lo, ASR, kBitsPerWord - 1));
+  b(&done, EQ);
+  LoadImmediate(result, ICData::kUint32Bit);  // Uint32
+  tst(hi, Operand(hi));
+  LoadImmediate(result, ICData::kInt64Bit, NE);  // Int64
+  Bind(&done);
+}
+
+
+void Assembler::UpdateRangeFeedback(Register value,
+                                    intptr_t idx,
+                                    Register ic_data,
+                                    Register scratch1,
+                                    Register scratch2,
+                                    Label* miss) {
+  ComputeRange(scratch1, value, scratch2, miss);
+  ldr(scratch2, FieldAddress(ic_data, ICData::range_feedback_offset()));
+  orr(scratch2,
+      scratch2,
+      Operand(scratch1, LSL, ICData::kBitsPerRangeFeedback * idx));

[zra, 2014/12/11 04:29:33]

Maybe assert that (ICData::kBitsPerRangeFeedback * idx) < 32?

[Vyacheslav Egorov (Google), 2014/12/11 13:06:25]

Done.

+  str(scratch2, FieldAddress(ic_data, ICData::range_feedback_offset()));
+}
+
+
 static bool CanEncodeBranchOffset(int32_t offset) {
   ASSERT(Utils::IsAligned(offset, 4));
   return Utils::IsInt(Utils::CountOneBits(kBranchOffsetMask), offset);