Put more constants in movw/movt instructions

src/arm/assembler-arm.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 1169 matching lines @@
 
   void pop() {
     add(sp, sp, Operand(kPointerSize));
   }
 
   // Jump unconditionally to given label.
   void jmp(Label* L) { b(L, al); }
 
   bool predictable_code_size() const { return predictable_code_size_; }
 
-  static bool allow_immediate_constant_pool_loads(
+  static bool use_immediate_constant_pool_loads(
       const Assembler* assembler) {
+#ifdef USE_BLX
     return CpuFeatures::IsSupported(MOVW_MOVT_IMMEDIATE_LOADS) &&
         (assembler == NULL || !assembler->predictable_code_size());
+#else
+    // If not using BLX, all loads from the constant pool cannot be immediate,
+    // because the ldr pc, [pc + #xxxx] used for calls must be a single
+    // instruction and cannot be easily distinguished out of context from
+    // other loads that could use movw/movt.
+    return false;
+#endif
   }
 
   // Check the code size generated from label to here.
   int SizeOfCodeGeneratedSince(Label* label) {
     return pc_offset() - label->pos();
   }
 
   // Check the number of instructions generated from label to here.
   int InstructionsGeneratedSince(Label* label) {
     return SizeOfCodeGeneratedSince(label) / kInstrSize;
@@ skipping 316 matching lines @@
 
  private:
   Assembler* asm_;
   bool old_value_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_ASSEMBLER_ARM_H_