PPC/s390: [builtins] Fix MathMaxMin on arm and arm64

src/ppc/builtins-ppc.cc

 // Copyright 2014 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.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 108 matching lines @@
   // tail call a stub
   __ LoadRoot(r5, Heap::kUndefinedValueRootIndex);
   ArrayConstructorStub stub(masm->isolate());
   __ TailCallStub(&stub);
 }
 
 
 // static
 void Builtins::Generate_MathMaxMin(MacroAssembler* masm, MathMaxMinKind kind) {
   // ----------- S t a t e -------------
-  //  -- r3                 : number of arguments
-  //  -- r4                 : function
-  //  -- cp                 : context
-  //  -- lr                 : return address
-  //  -- sp[(argc - n) * 8] : arg[n] (zero-based)
-  //  -- sp[(argc + 1) * 8] : receiver
+  //  -- r3                     : number of arguments
+  //  -- r4                     : function
+  //  -- cp                     : context
+  //  -- lr                     : return address
+  //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
+  //  -- sp[argc * 4]           : receiver
   // -----------------------------------
   Condition const cond_done = (kind == MathMaxMinKind::kMin) ? lt : gt;
   Heap::RootListIndex const root_index =
       (kind == MathMaxMinKind::kMin) ? Heap::kInfinityValueRootIndex
                                      : Heap::kMinusInfinityValueRootIndex;
   DoubleRegister const reg = (kind == MathMaxMinKind::kMin) ? d2 : d1;
 
   // Load the accumulator with the default return value (either -Infinity or
   // +Infinity), with the tagged value in r8 and the double value in d1.
   __ LoadRoot(r8, root_index);
   __ lfd(d1, FieldMemOperand(r8, HeapNumber::kValueOffset));
 
   // Setup state for loop
   // r5: address of arg[0] + kPointerSize
   // r6: number of slots to drop at exit (arguments + receiver)
   __ addi(r7, r3, Operand(1));
 
   Label done_loop, loop;
+  __ mr(r7, r3);
   __ bind(&loop);
   {
     // Check if all parameters done.
-    __ subi(r3, r3, Operand(1));
-    __ cmpi(r3, Operand::Zero());
+    __ subi(r7, r7, Operand(1));
+    __ cmpi(r7, Operand::Zero());
     __ blt(&done_loop);
 
     // Load the next parameter tagged value into r5.
-    __ ShiftLeftImm(r5, r3, Operand(kPointerSizeLog2));
+    __ ShiftLeftImm(r5, r7, Operand(kPointerSizeLog2));
     __ LoadPX(r5, MemOperand(sp, r5));
 
     // Load the double value of the parameter into d2, maybe converting the
     // parameter to a number first using the ToNumber builtin if necessary.
     Label convert, convert_smi, convert_number, done_convert;
     __ bind(&convert);
     __ JumpIfSmi(r5, &convert_smi);
     __ LoadP(r6, FieldMemOperand(r5, HeapObject::kMapOffset));
     __ JumpIfRoot(r6, Heap::kHeapNumberMapRootIndex, &convert_number);
     {
@@ skipping 53 matching lines @@
 
     // At least one side is NaN, which means that the result will be NaN too.
     // We still need to visit the rest of the arguments.
     __ bind(&compare_nan);
     __ LoadRoot(r8, Heap::kNanValueRootIndex);
     __ lfd(d1, FieldMemOperand(r8, HeapNumber::kValueOffset));
     __ b(&loop);
   }
 
   __ bind(&done_loop);
+  // Drop all slots, including the receiver.
+  __ addi(r3, r3, Operand(1));
+  __ Drop(r3);
   __ mr(r3, r8);
-  __ Drop(r7);
   __ Ret();
 }
 
 // static
 void Builtins::Generate_NumberConstructor(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- r3                     : number of arguments
   //  -- r4                     : constructor function
   //  -- lr                     : return address
   //  -- sp[(argc - n - 1) * 4] : arg[n] (zero based)
@@ skipping 2753 matching lines @@
     __ bkpt(0);
   }
 }
 
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_PPC