Intrinsify natural word size typed array getters on IA32 and X64

runtime/vm/intrinsifier_ia32.cc

Index: runtime/vm/intrinsifier_ia32.cc
diff --git a/runtime/vm/intrinsifier_ia32.cc b/runtime/vm/intrinsifier_ia32.cc
index 7760a931109937c73def80400eaa0f8edcb0bac1..834cf5f02b2cc32ab35487e77794b72da76574ae 100644
--- a/runtime/vm/intrinsifier_ia32.cc
+++ b/runtime/vm/intrinsifier_ia32.cc
@@ -564,11 +564,55 @@ bool Intrinsifier::Uint16Array_getIndexed(Assembler* assembler) {
 
 
 bool Intrinsifier::Int32Array_getIndexed(Assembler* assembler) {
+  Label fall_through;
+  TestByteArrayIndex(assembler, &fall_through);
+  // After TestByteArrayIndex:
+  // * EAX has the base address of the byte array.
+  // * EBX has the index into the array.
+  // EBX contains the SMI index which is shifted left by 1.
+  // This shift means we only multiply the index by 2 not 4 (sizeof Int32).
+  __ movl(EAX, FieldAddress(EAX,
+                            EBX,
+                            TIMES_2,
+                            Int32Array::data_offset()));
+  // Verify that the signed value in EAX can fit inside a Smi.
+  __ cmpl(EAX, Immediate(0xC0000000));
+  __ j(NEGATIVE, &fall_through, Assembler::kNearJump);  // Won't fit Smi.
+  __ SmiTag(EAX);
+  __ ret();
+  __ Bind(&fall_through);
   return false;
 }
 
 
 bool Intrinsifier::Uint32Array_getIndexed(Assembler* assembler) {
+  Label fall_through;
+  TestByteArrayIndex(assembler, &fall_through);
+  // After TestByteArrayIndex:
+  // * EAX has the base address of the byte array.
+  // * EBX has the index into the array.
+  // EBX contains the SMI index which is shifted left by 1.
+  // This shift means we only multiply the index by 2 not 4 (sizeof Uint32).
+  __ movl(EAX, FieldAddress(EAX,
+                            EBX,
+                            TIMES_2,
+                            Uint32Array::data_offset()));
+    // Verify that the unsigned value in EAX can be stored in a Smi.
+  __ testl(EAX,  Immediate(0xC0000000));
+  __ j(NOT_ZERO, &fall_through, Assembler::kNearJump);  // Won't fit Smi.
+  __ SmiTag(EAX);
+  __ ret();
+  __ Bind(&fall_through);
+  return false;
+}
+
+
+bool Intrinsifier::Int64Array_getIndexed(Assembler* assembler) {
+  return false;
+}
+
+
+bool Intrinsifier::Uint64Array_getIndexed(Assembler* assembler) {
   return false;
 }