[wasm][mips] Save FP & PC when calling C functions

Ported changes from the following CLs to mips/mips64:
  - https://chromium-review.googlesource.com/c/v8/v8/+/2066964
  - https://chromium-review.googlesource.com/c/v8/v8/+/2071866
  - https://chromium-review.googlesource.com/c/v8/v8/+/2080242

This change is needed for profiling of Wasm code that calls C-function
to ignore the C-stack above the Wasm stack that otherwise couldn't be
parsed otherwise.

Bug: chromium:1045860
Change-Id: Ifdce5be6c5373714a67b3ce8d8c4f0a18f63b6fa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2082566Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Emanuel Ziegler <ecmziegler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66785}

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

@@ -5375,31 +5375,38 @@ void TurboAssembler::CallCFunctionHelper(Register function_base,
 
     // Save the frame pointer and PC so that the stack layout remains iterable,
     // even without an ExitFrame which normally exists between JS and C frames.
-    if (isolate() != nullptr) {
-      // 't' registers are caller-saved so this is safe as a scratch register.
-      Register scratch1 = t4;
-      Register scratch2 = t5;
-      DCHECK(!AreAliased(scratch1, scratch2, function_base));
-
-      Label get_pc;
-      mov(scratch1, ra);
-      Call(&get_pc);
-
-      bind(&get_pc);
-      mov(scratch2, ra);
-      mov(ra, scratch1);
-
-      li(scratch1, ExternalReference::fast_c_call_caller_pc_address(isolate()));
-      sw(scratch2, MemOperand(scratch1));
-      li(scratch1, ExternalReference::fast_c_call_caller_fp_address(isolate()));
-      sw(fp, MemOperand(scratch1));
+    // 't' registers are caller-saved so this is safe as a scratch register.
+    Register pc_scratch = t4;
+    Register scratch = t5;
+    DCHECK(!AreAliased(pc_scratch, scratch, function_base));
+
+    mov(scratch, ra);
+    nal();
+    mov(pc_scratch, ra);
+    mov(ra, scratch);
+
+    // See x64 code for reasoning about how to address the isolate data fields.
+    if (root_array_available()) {
+      sw(pc_scratch, MemOperand(kRootRegister,
+                                IsolateData::fast_c_call_caller_pc_offset()));
+      sw(fp, MemOperand(kRootRegister,
+                        IsolateData::fast_c_call_caller_fp_offset()));
+    } else {
+      DCHECK_NOT_NULL(isolate());
+      li(scratch, ExternalReference::fast_c_call_caller_pc_address(isolate()));
+      sw(pc_scratch, MemOperand(scratch));
+      li(scratch, ExternalReference::fast_c_call_caller_fp_address(isolate()));
+      sw(fp, MemOperand(scratch));
     }
 
     Call(function_base, function_offset);
 
-    if (isolate() != nullptr) {
-      // We don't unset the PC; the FP is the source of truth.
-      Register scratch = t4;
+    // We don't unset the PC; the FP is the source of truth.
+    if (root_array_available()) {
+      sw(zero_reg, MemOperand(kRootRegister,
+                              IsolateData::fast_c_call_caller_fp_offset()));
+    } else {
+      DCHECK_NOT_NULL(isolate());
       li(scratch, ExternalReference::fast_c_call_caller_fp_address(isolate()));
       sw(zero_reg, MemOperand(scratch));
     }

src/codegen/mips64/macro-assembler-mips64.cc

@@ -5699,31 +5699,38 @@ void TurboAssembler::CallCFunctionHelper(Register function,
 
     // Save the frame pointer and PC so that the stack layout remains iterable,
     // even without an ExitFrame which normally exists between JS and C frames.
-    if (isolate() != nullptr) {
-      // 't' registers are caller-saved so this is safe as a scratch register.
-      Register scratch1 = t1;
-      Register scratch2 = t2;
-      DCHECK(!AreAliased(scratch1, scratch2, function));
-
-      Label get_pc;
-      mov(scratch1, ra);
-      Call(&get_pc);
-
-      bind(&get_pc);
-      mov(scratch2, ra);
-      mov(ra, scratch1);
-
-      li(scratch1, ExternalReference::fast_c_call_caller_pc_address(isolate()));
-      Sd(scratch2, MemOperand(scratch1));
-      li(scratch1, ExternalReference::fast_c_call_caller_fp_address(isolate()));
-      Sd(fp, MemOperand(scratch1));
+    // 't' registers are caller-saved so this is safe as a scratch register.
+    Register pc_scratch = t1;
+    Register scratch = t2;
+    DCHECK(!AreAliased(pc_scratch, scratch, function));
+
+    mov(scratch, ra);
+    nal();
+    mov(pc_scratch, ra);
+    mov(ra, scratch);
+
+    // See x64 code for reasoning about how to address the isolate data fields.
+    if (root_array_available()) {
+      Sd(pc_scratch, MemOperand(kRootRegister,
+                                IsolateData::fast_c_call_caller_pc_offset()));
+      Sd(fp, MemOperand(kRootRegister,
+                        IsolateData::fast_c_call_caller_fp_offset()));
+    } else {
+      DCHECK_NOT_NULL(isolate());
+      li(scratch, ExternalReference::fast_c_call_caller_pc_address(isolate()));
+      Sd(pc_scratch, MemOperand(scratch));
+      li(scratch, ExternalReference::fast_c_call_caller_fp_address(isolate()));
+      Sd(fp, MemOperand(scratch));
     }
 
     Call(function);
 
-    if (isolate() != nullptr) {
-      // We don't unset the PC; the FP is the source of truth.
-      Register scratch = t1;
+    // We don't unset the PC; the FP is the source of truth.
+    if (root_array_available()) {
+      Sd(zero_reg, MemOperand(kRootRegister,
+                              IsolateData::fast_c_call_caller_fp_offset()));
+    } else {
+      DCHECK_NOT_NULL(isolate());
       li(scratch, ExternalReference::fast_c_call_caller_fp_address(isolate()));
       Sd(zero_reg, MemOperand(scratch));
     }

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

@@ -787,7 +787,7 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       bool isWasmCapiFunction =
           linkage()->GetIncomingDescriptor()->IsWasmCapiFunction();
       // from start_call to return address.
-      int offset = 40;
+      int offset = __ root_array_available() ? 68 : 80;
 #if V8_HOST_ARCH_MIPS
       if (__ emit_debug_code()) {
         offset += 16;

src/compiler/backend/mips64/code-generator-mips64.cc

@@ -765,7 +765,7 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       bool isWasmCapiFunction =
           linkage()->GetIncomingDescriptor()->IsWasmCapiFunction();
       // from start_call to return address.
-      int offset = 48;
+      int offset = __ root_array_available() ? 76 : 88;
 #if V8_HOST_ARCH_MIPS64
       if (__ emit_debug_code()) {
         offset += 16;

src/regexp/mips/regexp-macro-assembler-mips.cc

@@ -106,6 +106,8 @@ RegExpMacroAssemblerMIPS::RegExpMacroAssemblerMIPS(Isolate* isolate, Zone* zone,
       backtrack_label_(),
       exit_label_(),
       internal_failure_label_() {
+  masm_->set_root_array_available(false);
+
   DCHECK_EQ(0, registers_to_save % 2);
   __ jmp(&entry_label_);   // We'll write the entry code later.
   // If the code gets too big or corrupted, an internal exception will be

src/regexp/mips64/regexp-macro-assembler-mips64.cc

@@ -142,6 +142,8 @@ RegExpMacroAssemblerMIPS::RegExpMacroAssemblerMIPS(Isolate* isolate, Zone* zone,
       backtrack_label_(),
       exit_label_(),
       internal_failure_label_() {
+  masm_->set_root_array_available(false);
+
   DCHECK_EQ(0, registers_to_save % 2);
   __ jmp(&entry_label_);   // We'll write the entry code later.
   // If the code gets too big or corrupted, an internal exception will be

test/unittests/assembler/turbo-assembler-mips-unittest.cc

@@ -22,14 +22,15 @@ class TurboAssemblerTest : public TestWithIsolate {};
 
 TEST_F(TurboAssemblerTest, TestHardAbort) {
   auto buffer = AllocateAssemblerBuffer();
-  TurboAssembler tasm(nullptr, AssemblerOptions{}, CodeObjectRequired::kNo,
+  TurboAssembler tasm(isolate(), AssemblerOptions{}, CodeObjectRequired::kNo,
                       buffer->CreateView());
+  __ set_root_array_available(false);
   __ set_abort_hard(true);
 
   __ Abort(AbortReason::kNoReason);
 
   CodeDesc desc;
-  tasm.GetCode(nullptr, &desc);
+  tasm.GetCode(isolate(), &desc);
   buffer->MakeExecutable();
   // We need an isolate here to execute in the simulator.
   auto f = GeneratedCode<void>::FromBuffer(isolate(), buffer->start());
@@ -39,8 +40,9 @@ TEST_F(TurboAssemblerTest, TestHardAbort) {
 
 TEST_F(TurboAssemblerTest, TestCheck) {
   auto buffer = AllocateAssemblerBuffer();
-  TurboAssembler tasm(nullptr, AssemblerOptions{}, CodeObjectRequired::kNo,
+  TurboAssembler tasm(isolate(), AssemblerOptions{}, CodeObjectRequired::kNo,
                       buffer->CreateView());
+  __ set_root_array_available(false);
   __ set_abort_hard(true);
 
   // Fail if the first parameter (in {a0}) is 17.
@@ -48,7 +50,7 @@ TEST_F(TurboAssemblerTest, TestCheck) {
   __ Ret();
 
   CodeDesc desc;
-  tasm.GetCode(nullptr, &desc);
+  tasm.GetCode(isolate(), &desc);
   buffer->MakeExecutable();
   // We need an isolate here to execute in the simulator.
   auto f = GeneratedCode<void, int>::FromBuffer(isolate(), buffer->start());

test/unittests/assembler/turbo-assembler-mips64-unittest.cc

@@ -22,14 +22,15 @@ class TurboAssemblerTest : public TestWithIsolate {};
 
 TEST_F(TurboAssemblerTest, TestHardAbort) {
   auto buffer = AllocateAssemblerBuffer();
-  TurboAssembler tasm(nullptr, AssemblerOptions{}, CodeObjectRequired::kNo,
+  TurboAssembler tasm(isolate(), AssemblerOptions{}, CodeObjectRequired::kNo,
                       buffer->CreateView());
+  __ set_root_array_available(false);
   __ set_abort_hard(true);
 
   __ Abort(AbortReason::kNoReason);
 
   CodeDesc desc;
-  tasm.GetCode(nullptr, &desc);
+  tasm.GetCode(isolate(), &desc);
   buffer->MakeExecutable();
   // We need an isolate here to execute in the simulator.
   auto f = GeneratedCode<void>::FromBuffer(isolate(), buffer->start());
@@ -39,8 +40,9 @@ TEST_F(TurboAssemblerTest, TestHardAbort) {
 
 TEST_F(TurboAssemblerTest, TestCheck) {
   auto buffer = AllocateAssemblerBuffer();
-  TurboAssembler tasm(nullptr, AssemblerOptions{}, CodeObjectRequired::kNo,
+  TurboAssembler tasm(isolate(), AssemblerOptions{}, CodeObjectRequired::kNo,
                       buffer->CreateView());
+  __ set_root_array_available(false);
   __ set_abort_hard(true);
 
   // Fail if the first parameter (in {a0}) is 17.
@@ -48,7 +50,7 @@ TEST_F(TurboAssemblerTest, TestCheck) {
   __ Ret();
 
   CodeDesc desc;
-  tasm.GetCode(nullptr, &desc);
+  tasm.GetCode(isolate(), &desc);
   buffer->MakeExecutable();
   // We need an isolate here to execute in the simulator.
   auto f = GeneratedCode<void, int>::FromBuffer(isolate(), buffer->start());