MIPS: Followup to '[turbofan] Add basic support for calling to (a subset of) C functions.'

src/compiler/mips/instruction-selector-mips.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.
 
 #include "src/base/adapters.h"
 #include "src/base/bits.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
@@ skipping 515 matching lines @@
   // Compute InstructionOperands for inputs and outputs.
   InitializeCallBuffer(node, &buffer, true, true);
 
   // Prepare for C function call.
   if (descriptor->IsCFunctionCall()) {
     Emit(kArchPrepareCallCFunction |
              MiscField::encode(static_cast<int>(descriptor->CParameterCount())),
          0, nullptr, 0, nullptr);
 
     // Poke any stack arguments.
-    int slot = kCArgSlotCount;
-    for (Node* node : buffer.pushed_nodes) {
-      Emit(kMipsStoreToStackSlot, g.NoOutput(), g.UseRegister(node),
-           g.TempImmediate(slot << kPointerSizeLog2));
-      ++slot;
+    for (size_t n = 0; n < buffer.pushed_nodes.size(); ++n) {
+      if (Node* node = buffer.pushed_nodes[n]) {
+        int const slot = static_cast<int>(n);
+        Emit(kMipsStoreToStackSlot, g.NoOutput(), g.UseRegister(node),
+             g.TempImmediate(slot << kPointerSizeLog2));
+      }
     }
   } else {
     // Possibly align stack here for functions.
     int push_count = buffer.pushed_nodes.size();
     if (push_count > 0) {
       Emit(kMipsStackClaim, g.NoOutput(),
            g.TempImmediate(push_count << kPointerSizeLog2));
     }
     int slot = buffer.pushed_nodes.size() - 1;
     for (Node* node : base::Reversed(buffer.pushed_nodes)) {
@@ skipping 554 matching lines @@
       IsFp64Mode()) {
     flags |= MachineOperatorBuilder::kFloat64RoundDown |
              MachineOperatorBuilder::kFloat64RoundTruncate;
   }
   return flags;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8