S390: Upstream changes from the past 2 weeks

src/crankshaft/s390/lithium-codegen-s390.cc

Index: src/crankshaft/s390/lithium-codegen-s390.cc
diff --git a/src/crankshaft/s390/lithium-codegen-s390.cc b/src/crankshaft/s390/lithium-codegen-s390.cc
index bb5286d8e7257a396754097822777d71c4d423b4..32784a167f180dc1f6b74ad4f370cb70b0dbaf0a 100644
--- a/src/crankshaft/s390/lithium-codegen-s390.cc
+++ b/src/crankshaft/s390/lithium-codegen-s390.cc
@@ -113,7 +113,7 @@ bool LCodeGen::GeneratePrologue() {
   info()->set_prologue_offset(prologue_offset);
   if (NeedsEagerFrame()) {
     if (info()->IsStub()) {
-      __ StubPrologue(ip, prologue_offset);
+      __ StubPrologue(StackFrame::STUB, ip, prologue_offset);
     } else {
       __ Prologue(info()->GeneratePreagedPrologue(), ip, prologue_offset);
     }
@@ -251,16 +251,14 @@ bool LCodeGen::GenerateDeferredCode() {
         DCHECK(info()->IsStub());
         frame_is_built_ = true;
         __ LoadSmiLiteral(scratch0(), Smi::FromInt(StackFrame::STUB));
-        __ PushFixedFrame(scratch0());
-        __ la(fp,
-              MemOperand(sp, StandardFrameConstants::kFixedFrameSizeFromFp));
+        __ PushCommonFrame(scratch0());
         Comment(";;; Deferred code");
       }
       code->Generate();
       if (NeedsDeferredFrame()) {
         Comment(";;; Destroy frame");
         DCHECK(frame_is_built_);
-        __ PopFixedFrame(ip);
+        __ PopCommonFrame(scratch0());
         frame_is_built_ = false;
       }
       __ b(code->exit());
@@ -308,7 +306,7 @@ bool LCodeGen::GenerateJumpTable() {
       if (table_entry->needs_frame) {
         DCHECK(!info()->saves_caller_doubles());
         Comment(";;; call deopt with frame");
-        __ PushFixedFrame();
+        __ PushCommonFrame();
         __ b(r14, &needs_frame);
       } else {
         __ b(r14, &call_deopt_entry);
@@ -325,7 +323,7 @@ bool LCodeGen::GenerateJumpTable() {
       DCHECK(info()->IsStub());
       __ LoadSmiLiteral(ip, Smi::FromInt(StackFrame::STUB));
       __ push(ip);
-      __ lay(fp, MemOperand(sp, StandardFrameConstants::kFixedFrameSizeFromFp));
+      DCHECK(info()->IsStub());
     }
 
     Comment(";;; call deopt");
@@ -2108,29 +2106,30 @@ void LCodeGen::DoBranch(LBranch* instr) {
       __ CmpP(ip, Operand::Zero());
       EmitBranch(instr, ne);
     } else {
-      ToBooleanStub::Types expected = instr->hydrogen()->expected_input_types();
+      ToBooleanICStub::Types expected =
+          instr->hydrogen()->expected_input_types();
       // Avoid deopts in the case where we've never executed this path before.
-      if (expected.IsEmpty()) expected = ToBooleanStub::Types::Generic();
+      if (expected.IsEmpty()) expected = ToBooleanICStub::Types::Generic();
 
-      if (expected.Contains(ToBooleanStub::UNDEFINED)) {
+      if (expected.Contains(ToBooleanICStub::UNDEFINED)) {
         // undefined -> false.
         __ CompareRoot(reg, Heap::kUndefinedValueRootIndex);
         __ beq(instr->FalseLabel(chunk_));
       }
-      if (expected.Contains(ToBooleanStub::BOOLEAN)) {
+      if (expected.Contains(ToBooleanICStub::BOOLEAN)) {
         // Boolean -> its value.
         __ CompareRoot(reg, Heap::kTrueValueRootIndex);
         __ beq(instr->TrueLabel(chunk_));
         __ CompareRoot(reg, Heap::kFalseValueRootIndex);
         __ beq(instr->FalseLabel(chunk_));
       }
-      if (expected.Contains(ToBooleanStub::NULL_TYPE)) {
+      if (expected.Contains(ToBooleanICStub::NULL_TYPE)) {
         // 'null' -> false.
         __ CompareRoot(reg, Heap::kNullValueRootIndex);
         __ beq(instr->FalseLabel(chunk_));
       }
 
-      if (expected.Contains(ToBooleanStub::SMI)) {
+      if (expected.Contains(ToBooleanICStub::SMI)) {
         // Smis: 0 -> false, all other -> true.
         __ CmpP(reg, Operand::Zero());
         __ beq(instr->FalseLabel(chunk_));
@@ -2153,13 +2152,13 @@ void LCodeGen::DoBranch(LBranch* instr) {
         }
       }
 
-      if (expected.Contains(ToBooleanStub::SPEC_OBJECT)) {
+      if (expected.Contains(ToBooleanICStub::SPEC_OBJECT)) {
         // spec object -> true.
         __ CompareInstanceType(map, ip, FIRST_JS_RECEIVER_TYPE);
         __ bge(instr->TrueLabel(chunk_));
       }
 
-      if (expected.Contains(ToBooleanStub::STRING)) {
+      if (expected.Contains(ToBooleanICStub::STRING)) {
         // String value -> false iff empty.
         Label not_string;
         __ CompareInstanceType(map, ip, FIRST_NONSTRING_TYPE);
@@ -2171,20 +2170,20 @@ void LCodeGen::DoBranch(LBranch* instr) {
         __ bind(&not_string);
       }
 
-      if (expected.Contains(ToBooleanStub::SYMBOL)) {
+      if (expected.Contains(ToBooleanICStub::SYMBOL)) {
         // Symbol value -> true.
         __ CompareInstanceType(map, ip, SYMBOL_TYPE);
         __ beq(instr->TrueLabel(chunk_));
       }
 
-      if (expected.Contains(ToBooleanStub::SIMD_VALUE)) {
+      if (expected.Contains(ToBooleanICStub::SIMD_VALUE)) {
         // SIMD value -> true.
         Label not_simd;
         __ CompareInstanceType(map, ip, SIMD128_VALUE_TYPE);
         __ beq(instr->TrueLabel(chunk_));
       }
 
-      if (expected.Contains(ToBooleanStub::HEAP_NUMBER)) {
+      if (expected.Contains(ToBooleanICStub::HEAP_NUMBER)) {
         // heap number -> false iff +0, -0, or NaN.
         Label not_heap_number;
         __ CompareRoot(map, Heap::kHeapNumberMapRootIndex);
@@ -2417,11 +2416,10 @@ void LCodeGen::DoStringCompareAndBranch(LStringCompareAndBranch* instr) {
   DCHECK(ToRegister(instr->left()).is(r3));
   DCHECK(ToRegister(instr->right()).is(r2));
 
-  Handle<Code> code = CodeFactory::StringCompare(isolate()).code();
+  Handle<Code> code = CodeFactory::StringCompare(isolate(), instr->op()).code();
   CallCode(code, RelocInfo::CODE_TARGET, instr);
-  __ CmpP(r2, Operand::Zero());
-
-  EmitBranch(instr, ComputeCompareCondition(instr->op()));
+  __ CompareRoot(r2, Heap::kTrueValueRootIndex);
+  EmitBranch(instr, eq);
 }
 
 static InstanceType TestType(HHasInstanceTypeAndBranch* instr) {
@@ -3162,8 +3160,9 @@ void LCodeGen::DoArgumentsElements(LArgumentsElements* instr) {
     // Check if the calling frame is an arguments adaptor frame.
     Label done, adapted;
     __ LoadP(scratch, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
-    __ LoadP(result,
-             MemOperand(scratch, StandardFrameConstants::kContextOffset));
+    __ LoadP(
+        result,
+        MemOperand(scratch, CommonFrameConstants::kContextOrFrameTypeOffset));
     __ CmpSmiLiteral(result, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
 
     // Result is the frame pointer for the frame if not adapted and for the real
@@ -3287,14 +3286,26 @@ void LCodeGen::DoApplyArguments(LApplyArguments* instr) {
   __ BranchOnCount(length, &loop);
 
   __ bind(&invoke);
+
+  InvokeFlag flag = CALL_FUNCTION;
+  if (instr->hydrogen()->tail_call_mode() == TailCallMode::kAllow) {
+    DCHECK(!info()->saves_caller_doubles());
+    // TODO(ishell): drop current frame before pushing arguments to the stack.
+    flag = JUMP_FUNCTION;
+    ParameterCount actual(r2);
+    // It is safe to use r5, r6 and r7 as scratch registers here given that
+    // 1) we are not going to return to caller function anyway,
+    // 2) r5 (new.target) will be initialized below.
+    PrepareForTailCall(actual, r5, r6, r7);
+  }
+
   DCHECK(instr->HasPointerMap());
   LPointerMap* pointers = instr->pointer_map();
   SafepointGenerator safepoint_generator(this, pointers, Safepoint::kLazyDeopt);
   // The number of arguments is stored in receiver which is r2, as expected
   // by InvokeFunction.
   ParameterCount actual(receiver);
-  __ InvokeFunction(function, no_reg, actual, CALL_FUNCTION,
-                    safepoint_generator);
+  __ InvokeFunction(function, no_reg, actual, flag, safepoint_generator);
 }
 
 void LCodeGen::DoPushArgument(LPushArgument* instr) {
@@ -3336,7 +3347,7 @@ void LCodeGen::DoDeclareGlobals(LDeclareGlobals* instr) {
 
 void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
                                  int formal_parameter_count, int arity,
-                                 LInstruction* instr) {
+                                 bool is_tail_call, LInstruction* instr) {
   bool dont_adapt_arguments =
       formal_parameter_count == SharedFunctionInfo::kDontAdaptArgumentsSentinel;
   bool can_invoke_directly =
@@ -3358,19 +3369,31 @@ void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
 
     // Invoke function.
     if (is_self_call) {
-      __ CallSelf();
+      Handle<Code> self(reinterpret_cast<Code**>(__ CodeObject().location()));
+      if (is_tail_call) {
+        __ Jump(self, RelocInfo::CODE_TARGET);
+      } else {
+        __ Call(self, RelocInfo::CODE_TARGET);
+      }
     } else {
       __ LoadP(ip, FieldMemOperand(function_reg, JSFunction::kCodeEntryOffset));
-      __ CallJSEntry(ip);
+      if (is_tail_call) {
+        __ JumpToJSEntry(ip);
+      } else {
+        __ CallJSEntry(ip);
+      }
     }
 
-    // Set up deoptimization.
-    RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
+    if (!is_tail_call) {
+      // Set up deoptimization.
+      RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
+    }
   } else {
     SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
-    ParameterCount count(arity);
+    ParameterCount actual(arity);
     ParameterCount expected(formal_parameter_count);
-    __ InvokeFunction(function_reg, expected, count, CALL_FUNCTION, generator);
+    InvokeFlag flag = is_tail_call ? JUMP_FUNCTION : CALL_FUNCTION;
+    __ InvokeFunction(function_reg, expected, actual, flag, generator);
   }
 }
 
@@ -3689,21 +3712,77 @@ void LCodeGen::DoMathClz32(LMathClz32* instr) {
   __ bind(&done);
 }
 
+void LCodeGen::PrepareForTailCall(const ParameterCount& actual,
+                                  Register scratch1, Register scratch2,
+                                  Register scratch3) {
+#if DEBUG
+  if (actual.is_reg()) {
+    DCHECK(!AreAliased(actual.reg(), scratch1, scratch2, scratch3));
+  } else {
+    DCHECK(!AreAliased(scratch1, scratch2, scratch3));
+  }
+#endif
+  if (FLAG_code_comments) {
+    if (actual.is_reg()) {
+      Comment(";;; PrepareForTailCall, actual: %s {", actual.reg().ToString());
+    } else {
+      Comment(";;; PrepareForTailCall, actual: %d {", actual.immediate());
+    }
+  }
+
+  // Check if next frame is an arguments adaptor frame.
+  Register caller_args_count_reg = scratch1;
+  Label no_arguments_adaptor, formal_parameter_count_loaded;
+  __ LoadP(scratch2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
+  __ LoadP(scratch3,
+           MemOperand(scratch2, StandardFrameConstants::kContextOffset));
+  __ CmpSmiLiteral(scratch3, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
+  __ bne(&no_arguments_adaptor);
+
+  // Drop current frame and load arguments count from arguments adaptor frame.
+  __ LoadRR(fp, scratch2);
+  __ LoadP(caller_args_count_reg,
+           MemOperand(fp, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ SmiUntag(caller_args_count_reg);
+  __ b(&formal_parameter_count_loaded);
+
+  __ bind(&no_arguments_adaptor);
+  // Load caller's formal parameter count
+  __ mov(caller_args_count_reg, Operand(info()->literal()->parameter_count()));
+
+  __ bind(&formal_parameter_count_loaded);
+  __ PrepareForTailCall(actual, caller_args_count_reg, scratch2, scratch3);
+
+  Comment(";;; }");
+}
+
 void LCodeGen::DoInvokeFunction(LInvokeFunction* instr) {
+  HInvokeFunction* hinstr = instr->hydrogen();
   DCHECK(ToRegister(instr->context()).is(cp));
   DCHECK(ToRegister(instr->function()).is(r3));
   DCHECK(instr->HasPointerMap());
 
-  Handle<JSFunction> known_function = instr->hydrogen()->known_function();
+  bool is_tail_call = hinstr->tail_call_mode() == TailCallMode::kAllow;
+
+  if (is_tail_call) {
+    DCHECK(!info()->saves_caller_doubles());
+    ParameterCount actual(instr->arity());
+    // It is safe to use r5, r6 and r7 as scratch registers here given that
+    // 1) we are not going to return to caller function anyway,
+    // 2) r5 (new.target) will be initialized below.
+    PrepareForTailCall(actual, r5, r6, r7);
+  }
+
+  Handle<JSFunction> known_function = hinstr->known_function();
   if (known_function.is_null()) {
     LPointerMap* pointers = instr->pointer_map();
     SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
-    ParameterCount count(instr->arity());
-    __ InvokeFunction(r3, no_reg, count, CALL_FUNCTION, generator);
+    ParameterCount actual(instr->arity());
+    InvokeFlag flag = is_tail_call ? JUMP_FUNCTION : CALL_FUNCTION;
+    __ InvokeFunction(r3, no_reg, actual, flag, generator);
   } else {
-    CallKnownFunction(known_function,
-                      instr->hydrogen()->formal_parameter_count(),
-                      instr->arity(), instr);
+    CallKnownFunction(known_function, hinstr->formal_parameter_count(),
+                      instr->arity(), is_tail_call, instr);
   }
 }