Revert "PPC/s390: [codegen] Removed ParameterCount class"

This reverts commit 2da05dfc.

Reason for revert: Will need to commit some of the changes as a port of  46648402

Original change's description:
> PPC/s390: [codegen] Removed ParameterCount class
> 
> Port 1e696896
> 
> Original Commit Message:
> 
>     It was used only with Register inputs, so we can replace its uses with
>     the Registers themselves.
> 
> R=​solanes@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
> BUG=
> LOG=N
> 
> Change-Id: I95c0e6fc19ea5f9579d022756a4693ea0140d2f7
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1890543
> Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
> Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
> Cr-Commit-Position: refs/heads/master@{#64661}

TBR=michael_dawson@ca.ibm.com,jyan@ca.ibm.com,joransiu@ca.ibm.com,miladfar@ca.ibm.com,solanes@chromium.org

Change-Id: I10f0a7f3c81f7c5c396df1e26ead50c5f8755231
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1891073Reviewed-by: Milad Farazmand <miladfar@ca.ibm.com>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#64662}

src/builtins/ppc/builtins-ppc.cc

@@ -144,7 +144,8 @@ void Generate_JSBuiltinsConstructStubHelper(MacroAssembler* masm) {
     // r6: new target
     {
       ConstantPoolUnavailableScope constant_pool_unavailable(masm);
-      __ InvokeFunction(r4, r6, r3, CALL_FUNCTION);
+      ParameterCount actual(r3);
+      __ InvokeFunction(r4, r6, actual, CALL_FUNCTION);
     }
 
     // Restore context from the frame.
@@ -299,7 +300,8 @@ void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {
     // Call the function.
     {
       ConstantPoolUnavailableScope constant_pool_unavailable(masm);
-      __ InvokeFunction(r4, r6, r3, CALL_FUNCTION);
+      ParameterCount actual(r3);
+      __ InvokeFunction(r4, r6, actual, CALL_FUNCTION);
     }
 
     // ----------- S t a t e -------------
@@ -2100,7 +2102,9 @@ void Builtins::Generate_CallFunction(MacroAssembler* masm,
 
   __ LoadHalfWord(
       r5, FieldMemOperand(r5, SharedFunctionInfo::kFormalParameterCountOffset));
-  __ InvokeFunctionCode(r4, no_reg, r5, r3, JUMP_FUNCTION);
+  ParameterCount actual(r3);
+  ParameterCount expected(r5);
+  __ InvokeFunctionCode(r4, no_reg, expected, actual, JUMP_FUNCTION);
 
   // The function is a "classConstructor", need to raise an exception.
   __ bind(&class_constructor);

src/builtins/s390/builtins-s390.cc

@@ -139,7 +139,8 @@ void Generate_JSBuiltinsConstructStubHelper(MacroAssembler* masm) {
     // r3: constructor function
     // r5: new target
 
-    __ InvokeFunction(r3, r5, r2, CALL_FUNCTION);
+    ParameterCount actual(r2);
+    __ InvokeFunction(r3, r5, actual, CALL_FUNCTION);
 
     // Restore context from the frame.
     __ LoadP(cp, MemOperand(fp, ConstructFrameConstants::kContextOffset));
@@ -292,7 +293,8 @@ void Builtins::Generate_JSConstructStubGeneric(MacroAssembler* masm) {
     __ bind(&no_args);
 
     // Call the function.
-    __ InvokeFunction(r3, r5, r2, CALL_FUNCTION);
+    ParameterCount actual(r2);
+    __ InvokeFunction(r3, r5, actual, CALL_FUNCTION);
 
     // ----------- S t a t e -------------
     //  --                 r0: constructor result
@@ -2158,7 +2160,9 @@ void Builtins::Generate_CallFunction(MacroAssembler* masm,
 
   __ LoadLogicalHalfWordP(
       r4, FieldMemOperand(r4, SharedFunctionInfo::kFormalParameterCountOffset));
-  __ InvokeFunctionCode(r3, no_reg, r4, r2, JUMP_FUNCTION);
+  ParameterCount actual(r2);
+  ParameterCount expected(r4);
+  __ InvokeFunctionCode(r3, no_reg, expected, actual, JUMP_FUNCTION);
 
   // The function is a "classConstructor", need to raise an exception.
   __ bind(&class_constructor);

src/codegen/ppc/macro-assembler-ppc.cc

@@ -1152,25 +1152,36 @@ void TurboAssembler::MovFromFloatParameter(const DoubleRegister dst) {
   Move(dst, d1);
 }
 
-void TurboAssembler::PrepareForTailCall(Register callee_args_count,
-                                        Register caller_args_count,
+void TurboAssembler::PrepareForTailCall(const ParameterCount& callee_args_count,
+                                        Register caller_args_count_reg,
                                         Register scratch0, Register scratch1) {
-  DCHECK(!AreAliased(callee_args_count, caller_args_count, scratch0, scratch1));
+#if DEBUG
+  if (callee_args_count.is_reg()) {
+    DCHECK(!AreAliased(callee_args_count.reg(), caller_args_count_reg, scratch0,
+                       scratch1));
+  } else {
+    DCHECK(!AreAliased(caller_args_count_reg, scratch0, scratch1));
+  }
+#endif
 
   // Calculate the end of destination area where we will put the arguments
   // after we drop current frame. We add kPointerSize to count the receiver
   // argument which is not included into formal parameters count.
   Register dst_reg = scratch0;
-  ShiftLeftImm(dst_reg, caller_args_count, Operand(kPointerSizeLog2));
+  ShiftLeftImm(dst_reg, caller_args_count_reg, Operand(kPointerSizeLog2));
   add(dst_reg, fp, dst_reg);
   addi(dst_reg, dst_reg,
        Operand(StandardFrameConstants::kCallerSPOffset + kPointerSize));
 
-  Register src_reg = caller_args_count;
+  Register src_reg = caller_args_count_reg;
   // Calculate the end of source area. +kPointerSize is for the receiver.
-  ShiftLeftImm(src_reg, callee_args_count, Operand(kPointerSizeLog2));
-  add(src_reg, sp, src_reg);
-  addi(src_reg, src_reg, Operand(kPointerSize));
+  if (callee_args_count.is_reg()) {
+    ShiftLeftImm(src_reg, callee_args_count.reg(), Operand(kPointerSizeLog2));
+    add(src_reg, sp, src_reg);
+    addi(src_reg, src_reg, Operand(kPointerSize));
+  } else {
+    Add(src_reg, sp, (callee_args_count.immediate() + 1) * kPointerSize, r0);
+  }
 
   if (FLAG_debug_code) {
     cmpl(src_reg, dst_reg);
@@ -1188,7 +1199,11 @@ void TurboAssembler::PrepareForTailCall(Register callee_args_count,
   // so they must be pre-decremented in the loop.
   Register tmp_reg = scratch1;
   Label loop;
-  addi(tmp_reg, callee_args_count, Operand(1));  // +1 for receiver
+  if (callee_args_count.is_reg()) {
+    addi(tmp_reg, callee_args_count.reg(), Operand(1));  // +1 for receiver
+  } else {
+    mov(tmp_reg, Operand(callee_args_count.immediate() + 1));
+  }
   mtctr(tmp_reg);
   bind(&loop);
   LoadPU(tmp_reg, MemOperand(src_reg, -kPointerSize));
@@ -1199,8 +1214,9 @@ void TurboAssembler::PrepareForTailCall(Register callee_args_count,
   mr(sp, dst_reg);
 }
 
-void MacroAssembler::InvokePrologue(Register expected, Register actual,
-                                    Label* done, bool* definitely_mismatches,
+void MacroAssembler::InvokePrologue(const ParameterCount& expected,
+                                    const ParameterCount& actual, Label* done,
+                                    bool* definitely_mismatches,
                                     InvokeFlag flag) {
   bool definitely_matches = false;
   *definitely_mismatches = false;
@@ -1220,8 +1236,34 @@ void MacroAssembler::InvokePrologue(Register expected, Register actual,
   //  DCHECK(actual.is_immediate() || actual.reg() == r3);
   //  DCHECK(expected.is_immediate() || expected.reg() == r5);
 
-  cmp(expected, actual);
-  beq(&regular_invoke);
+  if (expected.is_immediate()) {
+    DCHECK(actual.is_immediate());
+    mov(r3, Operand(actual.immediate()));
+    if (expected.immediate() == actual.immediate()) {
+      definitely_matches = true;
+    } else {
+      const int sentinel = SharedFunctionInfo::kDontAdaptArgumentsSentinel;
+      if (expected.immediate() == sentinel) {
+        // Don't worry about adapting arguments for builtins that
+        // don't want that done. Skip adaption code by making it look
+        // like we have a match between expected and actual number of
+        // arguments.
+        definitely_matches = true;
+      } else {
+        *definitely_mismatches = true;
+        mov(r5, Operand(expected.immediate()));
+      }
+    }
+  } else {
+    if (actual.is_immediate()) {
+      mov(r3, Operand(actual.immediate()));
+      cmpi(expected.reg(), Operand(actual.immediate()));
+      beq(&regular_invoke);
+    } else {
+      cmp(expected.reg(), actual.reg());
+      beq(&regular_invoke);
+    }
+  }
 
   if (!definitely_matches) {
     Handle<Code> adaptor = BUILTIN_CODE(isolate(), ArgumentsAdaptorTrampoline);
@@ -1238,7 +1280,8 @@ void MacroAssembler::InvokePrologue(Register expected, Register actual,
 }
 
 void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
-                                    Register expected, Register actual) {
+                                    const ParameterCount& expected,
+                                    const ParameterCount& actual) {
   Label skip_hook;
 
   ExternalReference debug_hook_active =
@@ -1251,14 +1294,22 @@ void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
 
   {
     // Load receiver to pass it later to DebugOnFunctionCall hook.
-    ShiftLeftImm(r7, actual, Operand(kPointerSizeLog2));
-    LoadPX(r7, MemOperand(sp, r7));
+    if (actual.is_reg()) {
+      ShiftLeftImm(r7, actual.reg(), Operand(kPointerSizeLog2));
+      LoadPX(r7, MemOperand(sp, r7));
+    } else {
+      LoadP(r7, MemOperand(sp, actual.immediate() << kPointerSizeLog2), r0);
+    }
     FrameScope frame(this,
                      has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
-    SmiTag(expected);
-    Push(expected);
-    SmiTag(actual);
-    Push(actual);
+    if (expected.is_reg()) {
+      SmiTag(expected.reg());
+      Push(expected.reg());
+    }
+    if (actual.is_reg()) {
+      SmiTag(actual.reg());
+      Push(actual.reg());
+    }
     if (new_target.is_valid()) {
       Push(new_target);
     }
@@ -1268,20 +1319,26 @@ void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
     if (new_target.is_valid()) {
       Pop(new_target);
     }
-    Pop(actual);
-    SmiUntag(actual);
-    Pop(expected);
-    SmiUntag(expected);
+    if (actual.is_reg()) {
+      Pop(actual.reg());
+      SmiUntag(actual.reg());
+    }
+    if (expected.is_reg()) {
+      Pop(expected.reg());
+      SmiUntag(expected.reg());
+    }
   }
   bind(&skip_hook);
 }
 
 void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
-                                        Register expected, Register actual,
+                                        const ParameterCount& expected,
+                                        const ParameterCount& actual,
                                         InvokeFlag flag) {
   // You can't call a function without a valid frame.
   DCHECK(flag == JUMP_FUNCTION || has_frame());
   DCHECK(function == r4);
+  DCHECK_IMPLIES(new_target.is_valid(), new_target == r6);
 
   // On function call, call into the debugger if necessary.
   CheckDebugHook(function, new_target, expected, actual);
@@ -1314,7 +1371,8 @@ void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
 }
 
 void MacroAssembler::InvokeFunction(Register fun, Register new_target,
-                                    Register actual, InvokeFlag flag) {
+                                    const ParameterCount& actual,
+                                    InvokeFlag flag) {
   // You can't call a function without a valid frame.
   DCHECK(flag == JUMP_FUNCTION || has_frame());
 
@@ -1330,7 +1388,24 @@ void MacroAssembler::InvokeFunction(Register fun, Register new_target,
                FieldMemOperand(
                    temp_reg, SharedFunctionInfo::kFormalParameterCountOffset));
 
-  InvokeFunctionCode(fun, new_target, expected_reg, actual, flag);
+  ParameterCount expected(expected_reg);
+  InvokeFunctionCode(fun, new_target, expected, actual, flag);
+}
+
+void MacroAssembler::InvokeFunction(Register function,
+                                    const ParameterCount& expected,
+                                    const ParameterCount& actual,
+                                    InvokeFlag flag) {
+  // You can't call a function without a valid frame.
+  DCHECK(flag == JUMP_FUNCTION || has_frame());
+
+  // Contract with called JS functions requires that function is passed in r4.
+  DCHECK(function == r4);
+
+  // Get the function and setup the context.
+  LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
+
+  InvokeFunctionCode(r4, no_reg, expected, actual, flag);
 }
 
 void MacroAssembler::MaybeDropFrames() {

src/codegen/ppc/macro-assembler-ppc.h

@@ -333,8 +333,8 @@ class V8_EXPORT_PRIVATE TurboAssembler : public TurboAssemblerBase {
                             Register scratch);
   void PrepareCallCFunction(int num_reg_arguments, Register scratch);
 
-  void PrepareForTailCall(Register callee_args_count,
-                          Register caller_args_count, Register scratch0,
+  void PrepareForTailCall(const ParameterCount& callee_args_count,
+                          Register caller_args_count_reg, Register scratch0,
                           Register scratch1);
 
   // There are two ways of passing double arguments on ARM, depending on
@@ -743,22 +743,27 @@ class V8_EXPORT_PRIVATE MacroAssembler : public TurboAssembler {
 
   // Removes current frame and its arguments from the stack preserving
   // the arguments and a return address pushed to the stack for the next call.
-  // Both |callee_args_count| and |caller_args_count| do not include
-  // receiver. |callee_args_count| is not modified. |caller_args_count|
+  // Both |callee_args_count| and |caller_args_count_reg| do not include
+  // receiver. |callee_args_count| is not modified, |caller_args_count_reg|
   // is trashed.
 
   // Invoke the JavaScript function code by either calling or jumping.
   void InvokeFunctionCode(Register function, Register new_target,
-                          Register expected, Register actual, InvokeFlag flag);
+                          const ParameterCount& expected,
+                          const ParameterCount& actual, InvokeFlag flag);
 
   // On function call, call into the debugger if necessary.
-  void CheckDebugHook(Register fun, Register new_target, Register expected,
-                      Register actual);
+  void CheckDebugHook(Register fun, Register new_target,
+                      const ParameterCount& expected,
+                      const ParameterCount& actual);
 
   // Invoke the JavaScript function in the given register. Changes the
   // current context to the context in the function before invoking.
-  void InvokeFunction(Register function, Register new_target, Register actual,
-                      InvokeFlag flag);
+  void InvokeFunction(Register function, Register new_target,
+                      const ParameterCount& actual, InvokeFlag flag);
+
+  void InvokeFunction(Register function, const ParameterCount& expected,
+                      const ParameterCount& actual, InvokeFlag flag);
 
   void DebugBreak();
   // Frame restart support
@@ -945,7 +950,8 @@ class V8_EXPORT_PRIVATE MacroAssembler : public TurboAssembler {
   static const int kSmiShift = kSmiTagSize + kSmiShiftSize;
 
   // Helper functions for generating invokes.
-  void InvokePrologue(Register expected, Register actual, Label* done,
+  void InvokePrologue(const ParameterCount& expected,
+                      const ParameterCount& actual, Label* done,
                       bool* definitely_mismatches, InvokeFlag flag);
 
   // Compute memory operands for safepoint stack slots.

src/codegen/s390/macro-assembler-s390.cc

@@ -1201,25 +1201,39 @@ void TurboAssembler::MovFromFloatParameter(const DoubleRegister dst) {
   Move(dst, d0);
 }
 
-void TurboAssembler::PrepareForTailCall(Register callee_args_count,
-                                        Register caller_args_count,
+void TurboAssembler::PrepareForTailCall(const ParameterCount& callee_args_count,
+                                        Register caller_args_count_reg,
                                         Register scratch0, Register scratch1) {
-  DCHECK(!AreAliased(callee_args_count, caller_args_count, scratch0, scratch1));
+#if DEBUG
+  if (callee_args_count.is_reg()) {
+    DCHECK(!AreAliased(callee_args_count.reg(), caller_args_count_reg, scratch0,
+                       scratch1));
+  } else {
+    DCHECK(!AreAliased(caller_args_count_reg, scratch0, scratch1));
+  }
+#endif
 
   // Calculate the end of destination area where we will put the arguments
   // after we drop current frame. We AddP kSystemPointerSize to count the
   // receiver argument which is not included into formal parameters count.
   Register dst_reg = scratch0;
-  ShiftLeftP(dst_reg, caller_args_count, Operand(kSystemPointerSizeLog2));
+  ShiftLeftP(dst_reg, caller_args_count_reg, Operand(kSystemPointerSizeLog2));
   AddP(dst_reg, fp, dst_reg);
   AddP(dst_reg, dst_reg,
        Operand(StandardFrameConstants::kCallerSPOffset + kSystemPointerSize));
 
-  Register src_reg = caller_args_count;
+  Register src_reg = caller_args_count_reg;
   // Calculate the end of source area. +kSystemPointerSize is for the receiver.
-  ShiftLeftP(src_reg, callee_args_count, Operand(kSystemPointerSizeLog2));
-  AddP(src_reg, sp, src_reg);
-  AddP(src_reg, src_reg, Operand(kSystemPointerSize));
+  if (callee_args_count.is_reg()) {
+    ShiftLeftP(src_reg, callee_args_count.reg(),
+               Operand(kSystemPointerSizeLog2));
+    AddP(src_reg, sp, src_reg);
+    AddP(src_reg, src_reg, Operand(kSystemPointerSize));
+  } else {
+    mov(src_reg,
+        Operand((callee_args_count.immediate() + 1) * kSystemPointerSize));
+    AddP(src_reg, src_reg, sp);
+  }
 
   if (FLAG_debug_code) {
     CmpLogicalP(src_reg, dst_reg);
@@ -1237,7 +1251,11 @@ void TurboAssembler::PrepareForTailCall(Register callee_args_count,
   // so they must be pre-decremented in the loop.
   Register tmp_reg = scratch1;
   Label loop;
-  AddP(tmp_reg, callee_args_count, Operand(1));  // +1 for receiver
+  if (callee_args_count.is_reg()) {
+    AddP(tmp_reg, callee_args_count.reg(), Operand(1));  // +1 for receiver
+  } else {
+    mov(tmp_reg, Operand(callee_args_count.immediate() + 1));
+  }
   LoadRR(r1, tmp_reg);
   bind(&loop);
   LoadP(tmp_reg, MemOperand(src_reg, -kSystemPointerSize));
@@ -1250,8 +1268,9 @@ void TurboAssembler::PrepareForTailCall(Register callee_args_count,
   LoadRR(sp, dst_reg);
 }
 
-void MacroAssembler::InvokePrologue(Register expected, Register actual,
-                                    Label* done, bool* definitely_mismatches,
+void MacroAssembler::InvokePrologue(const ParameterCount& expected,
+                                    const ParameterCount& actual, Label* done,
+                                    bool* definitely_mismatches,
                                     InvokeFlag flag) {
   bool definitely_matches = false;
   *definitely_mismatches = false;
@@ -1268,11 +1287,37 @@ void MacroAssembler::InvokePrologue(Register expected, Register actual,
   // passed in registers.
 
   // ARM has some sanity checks as per below, considering add them for S390
-  DCHECK(actual == r2);
-  DCHECK(expected == r4);
-
-  CmpP(expected, actual);
-  beq(&regular_invoke);
+  DCHECK(actual.is_immediate() || actual.reg() == r2);
+  DCHECK(expected.is_immediate() || expected.reg() == r4);
+
+  if (expected.is_immediate()) {
+    DCHECK(actual.is_immediate());
+    mov(r2, Operand(actual.immediate()));
+    if (expected.immediate() == actual.immediate()) {
+      definitely_matches = true;
+    } else {
+      const int sentinel = SharedFunctionInfo::kDontAdaptArgumentsSentinel;
+      if (expected.immediate() == sentinel) {
+        // Don't worry about adapting arguments for builtins that
+        // don't want that done. Skip adaption code by making it look
+        // like we have a match between expected and actual number of
+        // arguments.
+        definitely_matches = true;
+      } else {
+        *definitely_mismatches = true;
+        mov(r4, Operand(expected.immediate()));
+      }
+    }
+  } else {
+    if (actual.is_immediate()) {
+      mov(r2, Operand(actual.immediate()));
+      CmpPH(expected.reg(), Operand(actual.immediate()));
+      beq(&regular_invoke);
+    } else {
+      CmpP(expected.reg(), actual.reg());
+      beq(&regular_invoke);
+    }
+  }
 
   if (!definitely_matches) {
     Handle<Code> adaptor = BUILTIN_CODE(isolate(), ArgumentsAdaptorTrampoline);
@@ -1289,7 +1334,8 @@ void MacroAssembler::InvokePrologue(Register expected, Register actual,
 }
 
 void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
-                                    Register expected, Register actual) {
+                                    const ParameterCount& expected,
+                                    const ParameterCount& actual) {
   Label skip_hook;
 
   ExternalReference debug_hook_active =
@@ -1300,14 +1346,23 @@ void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
 
   {
     // Load receiver to pass it later to DebugOnFunctionCall hook.
-    ShiftLeftP(r6, actual, Operand(kSystemPointerSizeLog2));
-    LoadP(r6, MemOperand(sp, r6));
+    if (actual.is_reg()) {
+      ShiftLeftP(r6, actual.reg(), Operand(kSystemPointerSizeLog2));
+      LoadP(r6, MemOperand(sp, r6));
+    } else {
+      LoadP(r6, MemOperand(sp, actual.immediate() << kSystemPointerSizeLog2),
+            ip);
+    }
     FrameScope frame(this,
                      has_frame() ? StackFrame::NONE : StackFrame::INTERNAL);
-    SmiTag(expected);
-    Push(expected);
-    SmiTag(actual);
-    Push(actual);
+    if (expected.is_reg()) {
+      SmiTag(expected.reg());
+      Push(expected.reg());
+    }
+    if (actual.is_reg()) {
+      SmiTag(actual.reg());
+      Push(actual.reg());
+    }
     if (new_target.is_valid()) {
       Push(new_target);
     }
@@ -1317,21 +1372,27 @@ void MacroAssembler::CheckDebugHook(Register fun, Register new_target,
     if (new_target.is_valid()) {
       Pop(new_target);
     }
-    Pop(actual);
-    SmiUntag(actual);
-    Pop(expected);
-    SmiUntag(expected);
+    if (actual.is_reg()) {
+      Pop(actual.reg());
+      SmiUntag(actual.reg());
+    }
+    if (expected.is_reg()) {
+      Pop(expected.reg());
+      SmiUntag(expected.reg());
+    }
   }
   bind(&skip_hook);
 }
 
 void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
-                                        Register expected, Register actual,
+                                        const ParameterCount& expected,
+                                        const ParameterCount& actual,
                                         InvokeFlag flag) {
   // You can't call a function without a valid frame.
   DCHECK(flag == JUMP_FUNCTION || has_frame());
 
   DCHECK(function == r3);
+  DCHECK_IMPLIES(new_target.is_valid(), new_target == r5);
 
   // On function call, call into the debugger if necessary.
   CheckDebugHook(function, new_target, expected, actual);
@@ -1364,7 +1425,8 @@ void MacroAssembler::InvokeFunctionCode(Register function, Register new_target,
 }
 
 void MacroAssembler::InvokeFunction(Register fun, Register new_target,
-                                    Register actual, InvokeFlag flag) {
+                                    const ParameterCount& actual,
+                                    InvokeFlag flag) {
   // You can't call a function without a valid frame.
   DCHECK(flag == JUMP_FUNCTION || has_frame());
 
@@ -1380,7 +1442,24 @@ void MacroAssembler::InvokeFunction(Register fun, Register new_target,
       FieldMemOperand(temp_reg,
                       SharedFunctionInfo::kFormalParameterCountOffset));
 
-  InvokeFunctionCode(fun, new_target, expected_reg, actual, flag);
+  ParameterCount expected(expected_reg);
+  InvokeFunctionCode(fun, new_target, expected, actual, flag);
+}
+
+void MacroAssembler::InvokeFunction(Register function,
+                                    const ParameterCount& expected,
+                                    const ParameterCount& actual,
+                                    InvokeFlag flag) {
+  // You can't call a function without a valid frame.
+  DCHECK(flag == JUMP_FUNCTION || has_frame());
+
+  // Contract with called JS functions requires that function is passed in r3.
+  DCHECK(function == r3);
+
+  // Get the function and setup the context.
+  LoadP(cp, FieldMemOperand(r3, JSFunction::kContextOffset));
+
+  InvokeFunctionCode(r3, no_reg, expected, actual, flag);
 }
 
 void MacroAssembler::MaybeDropFrames() {

src/codegen/s390/macro-assembler-s390.h

@@ -804,8 +804,8 @@ class V8_EXPORT_PRIVATE TurboAssembler : public TurboAssemblerBase {
 #endif
   }
 
-  void PrepareForTailCall(Register callee_args_count,
-                          Register caller_args_count, Register scratch0,
+  void PrepareForTailCall(const ParameterCount& callee_args_count,
+                          Register caller_args_count_reg, Register scratch0,
                           Register scratch1);
 
   // ---------------------------------------------------------------------------
@@ -1119,22 +1119,27 @@ class V8_EXPORT_PRIVATE MacroAssembler : public TurboAssembler {
 
   // Removes current frame and its arguments from the stack preserving
   // the arguments and a return address pushed to the stack for the next call.
-  // Both |callee_args_count| and |caller_args_count| do not include
-  // receiver. |callee_args_count| is not modified. |caller_args_count|
+  // Both |callee_args_count| and |caller_args_count_reg| do not include
+  // receiver. |callee_args_count| is not modified, |caller_args_count_reg|
   // is trashed.
 
   // Invoke the JavaScript function code by either calling or jumping.
   void InvokeFunctionCode(Register function, Register new_target,
-                          Register expected, Register actual, InvokeFlag flag);
+                          const ParameterCount& expected,
+                          const ParameterCount& actual, InvokeFlag flag);
 
   // On function call, call into the debugger if necessary.
-  void CheckDebugHook(Register fun, Register new_target, Register expected,
-                      Register actual);
+  void CheckDebugHook(Register fun, Register new_target,
+                      const ParameterCount& expected,
+                      const ParameterCount& actual);
 
   // Invoke the JavaScript function in the given register. Changes the
   // current context to the context in the function before invoking.
-  void InvokeFunction(Register function, Register new_target, Register actual,
-                      InvokeFlag flag);
+  void InvokeFunction(Register function, Register new_target,
+                      const ParameterCount& actual, InvokeFlag flag);
+
+  void InvokeFunction(Register function, const ParameterCount& expected,
+                      const ParameterCount& actual, InvokeFlag flag);
 
   // Frame restart support
   void MaybeDropFrames();
@@ -1271,7 +1276,8 @@ class V8_EXPORT_PRIVATE MacroAssembler : public TurboAssembler {
  private:
   static const int kSmiShift = kSmiTagSize + kSmiShiftSize;
   // Helper functions for generating invokes.
-  void InvokePrologue(Register expected, Register actual, Label* done,
+  void InvokePrologue(const ParameterCount& expected,
+                      const ParameterCount& actual, Label* done,
                       bool* definitely_mismatches, InvokeFlag flag);
 
   // Compute memory operands for safepoint stack slots.

src/compiler/backend/ppc/code-generator-ppc.cc

@@ -704,7 +704,9 @@ void CodeGenerator::AssemblePopArgumentsAdaptorFrame(Register args_reg,
            MemOperand(fp, ArgumentsAdaptorFrameConstants::kLengthOffset));
   __ SmiUntag(caller_args_count_reg);
 
-  __ PrepareForTailCall(args_reg, caller_args_count_reg, scratch2, scratch3);
+  ParameterCount callee_args_count(args_reg);
+  __ PrepareForTailCall(callee_args_count, caller_args_count_reg, scratch2,
+                        scratch3);
   __ bind(&done);
 }
 

src/compiler/backend/s390/code-generator-s390.cc

@@ -1193,7 +1193,9 @@ void CodeGenerator::AssemblePopArgumentsAdaptorFrame(Register args_reg,
            MemOperand(fp, ArgumentsAdaptorFrameConstants::kLengthOffset));
   __ SmiUntag(caller_args_count_reg);
 
-  __ PrepareForTailCall(args_reg, caller_args_count_reg, scratch2, scratch3);
+  ParameterCount callee_args_count(args_reg);
+  __ PrepareForTailCall(callee_args_count, caller_args_count_reg, scratch2,
+                        scratch3);
   __ bind(&done);
 }
 

src/debug/ppc/debug-ppc.cc

@@ -41,7 +41,9 @@ void DebugCodegen::GenerateFrameDropperTrampoline(MacroAssembler* masm) {
          FieldMemOperand(r3, SharedFunctionInfo::kFormalParameterCountOffset));
   __ mr(r5, r3);
 
-  __ InvokeFunction(r4, r5, r3, JUMP_FUNCTION);
+  ParameterCount dummy1(r5);
+  ParameterCount dummy2(r3);
+  __ InvokeFunction(r4, dummy1, dummy2, JUMP_FUNCTION);
 }
 
 const bool LiveEdit::kFrameDropperSupported = true;

src/debug/s390/debug-s390.cc

@@ -43,7 +43,9 @@ void DebugCodegen::GenerateFrameDropperTrampoline(MacroAssembler* masm) {
       r2, FieldMemOperand(r2, SharedFunctionInfo::kFormalParameterCountOffset));
   __ LoadRR(r4, r2);
 
-  __ InvokeFunction(r3, r4, r2, JUMP_FUNCTION);
+  ParameterCount dummy1(r4);
+  ParameterCount dummy2(r2);
+  __ InvokeFunction(r3, dummy1, dummy2, JUMP_FUNCTION);
 }
 
 const bool LiveEdit::kFrameDropperSupported = true;