Unify the stack layout for construct frames

src/arm/builtins-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM
 
 #include "src/codegen.h"
 #include "src/debug.h"
@@ skipping 606 matching lines @@
       // r2 is an AllocationSite. We are creating a memento from it, so we
       // need to increment the memento create count.
       __ ldr(r3, FieldMemOperand(r2,
                                  AllocationSite::kPretenureCreateCountOffset));
       __ add(r3, r3, Operand(Smi::FromInt(1)));
       __ str(r3, FieldMemOperand(r2,
                                  AllocationSite::kPretenureCreateCountOffset));
       __ bind(&count_incremented);
     }
 
+    __ pop(r1);  // Constructor function.
+
     __ push(r4);
     __ push(r4);
 
-    // Reload the number of arguments and the constructor from the stack.
+    // Reload the number of arguments from the stack.
     // sp[0]: receiver
     // sp[1]: receiver
-    // sp[2]: constructor function
-    // sp[3]: number of arguments (smi-tagged)
-    __ ldr(r1, MemOperand(sp, 2 * kPointerSize));
-    __ ldr(r3, MemOperand(sp, 3 * kPointerSize));
+    // sp[2]: number of arguments (smi-tagged)
+    __ ldr(r3, MemOperand(sp, 2 * kPointerSize));
 
     // Set up pointer to last argument.
     __ add(r2, fp, Operand(StandardFrameConstants::kCallerSPOffset));
 
     // Set up number of arguments for function call below
     __ SmiUntag(r0, r3);
 
     // Copy arguments and receiver to the expression stack.
     // r0: number of arguments
     // r1: constructor function
     // r2: address of last argument (caller sp)
     // r3: number of arguments (smi-tagged)
     // sp[0]: receiver
     // sp[1]: receiver
-    // sp[2]: constructor function
-    // sp[3]: number of arguments (smi-tagged)
+    // sp[2]: number of arguments (smi-tagged)
     Label loop, entry;
     __ b(&entry);
     __ bind(&loop);
     __ ldr(ip, MemOperand(r2, r3, LSL, kPointerSizeLog2 - 1));
     __ push(ip);
     __ bind(&entry);
     __ sub(r3, r3, Operand(2), SetCC);
     __ b(ge, &loop);
 
     // Call the function.
@@ skipping 10 matching lines @@
     }
 
     // Store offset of return address for deoptimizer.
     if (!is_api_function) {
       masm->isolate()->heap()->SetConstructStubDeoptPCOffset(masm->pc_offset());
     }
 
     // Restore context from the frame.
     // r0: result
     // sp[0]: receiver
-    // sp[1]: constructor function
-    // sp[2]: number of arguments (smi-tagged)
+    // sp[1]: number of arguments (smi-tagged)
     __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
 
     // If the result is an object (in the ECMA sense), we should get rid
     // of the receiver and use the result; see ECMA-262 section 13.2.2-7
     // on page 74.
     Label use_receiver, exit;
 
     // If the result is a smi, it is *not* an object in the ECMA sense.
     // r0: result
     // sp[0]: receiver (newly allocated object)
-    // sp[1]: constructor function
-    // sp[2]: number of arguments (smi-tagged)
+    // sp[1]: number of arguments (smi-tagged)
     __ JumpIfSmi(r0, &use_receiver);
 
     // If the type of the result (stored in its map) is less than
     // FIRST_SPEC_OBJECT_TYPE, it is not an object in the ECMA sense.
     __ CompareObjectType(r0, r1, r3, FIRST_SPEC_OBJECT_TYPE);
     __ b(ge, &exit);
 
     // Throw away the result of the constructor invocation and use the
     // on-stack receiver as the result.
     __ bind(&use_receiver);
     __ ldr(r0, MemOperand(sp));
 
     // Remove receiver from the stack, remove caller arguments, and
     // return.
     __ bind(&exit);
     // r0: result
     // sp[0]: receiver (newly allocated object)
-    // sp[1]: constructor function
-    // sp[2]: number of arguments (smi-tagged)
-    __ ldr(r1, MemOperand(sp, 2 * kPointerSize));
+    // sp[1]: number of arguments (smi-tagged)
+    __ ldr(r1, MemOperand(sp, kPointerSize));
 
     // Leave construct frame.
   }
 
   __ add(sp, sp, Operand(r1, LSL, kPointerSizeLog2 - 1));
   __ add(sp, sp, Operand(kPointerSize));
   __ IncrementCounter(isolate->counters()->constructed_objects(), 1, r1, r2);
   __ Jump(lr);
 }
 
@@ skipping 1083 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM