[turbofan] Canonicalize return sequence for JSFunctions.

This optimization is already implemented in fullcodegen, and
basically makes sure that we do not unecessarily blow up the
code with duplicated return sequences everywhere.

R=danno@chromium.org

Review URL: https://codereview.chromium.org/1211373002

Cr-Commit-Position: refs/heads/master@{#29315}

src/compiler/arm/code-generator-arm.cc

@@ -1024,12 +1024,18 @@ void CodeGenerator::AssembleReturn() {
     __ LeaveFrame(StackFrame::MANUAL);
     __ Ret();
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ LeaveFrame(StackFrame::MANUAL);
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ Drop(pop_count);
-    __ Ret();
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ b(&return_label_);
+    } else {
+      __ bind(&return_label_);
+      __ LeaveFrame(StackFrame::MANUAL);
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ Drop(pop_count);
+      __ Ret();
+    }
   } else {
     __ Ret();
   }

src/compiler/arm64/code-generator-arm64.cc

@@ -1153,13 +1153,19 @@ void CodeGenerator::AssembleReturn() {
     __ Pop(fp, lr);
     __ Ret();
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ Mov(jssp, fp);
-    __ Pop(fp, lr);
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ Drop(pop_count);
-    __ Ret();
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ B(&return_label_);
+    } else {
+      __ Bind(&return_label_);
+      __ Mov(jssp, fp);
+      __ Pop(fp, lr);
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ Drop(pop_count);
+      __ Ret();
+    }
   } else {
     __ Ret();
   }

src/compiler/code-generator.h

@@ -172,6 +172,7 @@ class CodeGenerator final : public GapResolver::Assembler {
   InstructionSequence* const code_;
   CompilationInfo* const info_;
   Label* const labels_;
+  Label return_label_;
   RpoNumber current_block_;
   SourcePosition current_source_position_;
   MacroAssembler masm_;

src/compiler/ia32/code-generator-ia32.cc

@@ -1339,12 +1339,18 @@ void CodeGenerator::AssembleReturn() {
       __ ret(0);
     }
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ mov(esp, ebp);  // Move stack pointer back to frame pointer.
-    __ pop(ebp);       // Pop caller's frame pointer.
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ Ret(pop_count * kPointerSize, ebx);
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ jmp(&return_label_);
+    } else {
+      __ bind(&return_label_);
+      __ mov(esp, ebp);  // Move stack pointer back to frame pointer.
+      __ pop(ebp);       // Pop caller's frame pointer.
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ Ret(pop_count * kPointerSize, ebx);
+    }
   } else {
     __ ret(0);
   }

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

@@ -1141,12 +1141,18 @@ void CodeGenerator::AssembleReturn() {
     __ Pop(ra, fp);
     __ Ret();
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ mov(sp, fp);
-    __ Pop(ra, fp);
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ DropAndRet(pop_count);
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ Branch(&return_label_);
+    } else {
+      __ bind(&return_label_);
+      __ mov(sp, fp);
+      __ Pop(ra, fp);
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ DropAndRet(pop_count);
+    }
   } else {
     __ Ret();
   }

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

@@ -1214,12 +1214,18 @@ void CodeGenerator::AssembleReturn() {
     __ Pop(ra, fp);
     __ Ret();
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ mov(sp, fp);
-    __ Pop(ra, fp);
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ DropAndRet(pop_count);
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ Branch(&return_label_);
+    } else {
+      __ bind(&return_label_);
+      __ mov(sp, fp);
+      __ Pop(ra, fp);
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ DropAndRet(pop_count);
+    }
   } else {
     __ Ret();
   }

src/compiler/x64/code-generator-x64.cc

@@ -1538,12 +1538,18 @@ void CodeGenerator::AssembleReturn() {
       __ ret(0);
     }
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ movq(rsp, rbp);  // Move stack pointer back to frame pointer.
-    __ popq(rbp);       // Pop caller's frame pointer.
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ Ret(pop_count * kPointerSize, rbx);
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ jmp(&return_label_);
+    } else {
+      __ bind(&return_label_);
+      __ movq(rsp, rbp);  // Move stack pointer back to frame pointer.
+      __ popq(rbp);       // Pop caller's frame pointer.
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ Ret(pop_count * kPointerSize, rbx);
+    }
   } else {
     __ ret(0);
   }

src/compiler/x87/code-generator-x87.cc

@@ -1599,12 +1599,18 @@ void CodeGenerator::AssembleReturn() {
       __ ret(0);
     }
   } else if (descriptor->IsJSFunctionCall() || needs_frame_) {
-    __ mov(esp, ebp);  // Move stack pointer back to frame pointer.
-    __ pop(ebp);       // Pop caller's frame pointer.
-    int pop_count = descriptor->IsJSFunctionCall()
-                        ? static_cast<int>(descriptor->JSParameterCount())
-                        : 0;
-    __ Ret(pop_count * kPointerSize, ebx);
+    // Canonicalize JSFunction return sites for now.
+    if (return_label_.is_bound()) {
+      __ jmp(&return_label_);
+    } else {
+      __ bind(&return_label_);
+      __ mov(esp, ebp);  // Move stack pointer back to frame pointer.
+      __ pop(ebp);       // Pop caller's frame pointer.
+      int pop_count = descriptor->IsJSFunctionCall()
+                          ? static_cast<int>(descriptor->JSParameterCount())
+                          : 0;
+      __ Ret(pop_count * kPointerSize, ebx);
+    }
   } else {
     __ ret(0);
   }