[turbofan]: Fix tail calls edge cases and add tests

Review URL: https://codereview.chromium.org/1245523002

Cr-Commit-Position: refs/heads/master@{#29791}

src/compiler/linkage.cc

@@ -53,6 +53,25 @@ bool CallDescriptor::HasSameReturnLocationsAs(
 
 
 bool CallDescriptor::CanTailCall(const Node* node) const {
+  // Determine the number of stack parameters passed in
+  size_t stack_params = 0;
+  for (size_t i = 0; i < InputCount(); ++i) {
+    if (!GetInputLocation(i).is_register()) {
+      ++stack_params;
+    }
+  }
+  // Ensure the input linkage contains the stack parameters in the right order
+  size_t current_stack_param = 0;
+  for (size_t i = 0; i < InputCount(); ++i) {
+    if (!GetInputLocation(i).is_register()) {
+      if (GetInputLocation(i) !=
+          LinkageLocation(static_cast<int>(current_stack_param) -
+                          static_cast<int>(stack_params))) {
+        return false;
+      }
+      ++current_stack_param;
+    }
+  }
   // Tail calling is currently allowed if return locations match and all
   // parameters are either in registers or on the stack but match exactly in
   // number and content.
@@ -60,10 +79,9 @@ bool CallDescriptor::CanTailCall(const Node* node) const {
   if (!HasSameReturnLocationsAs(other)) return false;
   size_t current_input = 0;
   size_t other_input = 0;
-  size_t stack_parameter = 0;
   while (true) {
     if (other_input >= other->InputCount()) {
-      while (current_input <= InputCount()) {
+      while (current_input < InputCount()) {
         if (!GetInputLocation(current_input).is_register()) {
           return false;
         }
@@ -96,11 +114,12 @@ bool CallDescriptor::CanTailCall(const Node* node) const {
     if (input->opcode() != IrOpcode::kParameter) {
       return false;
     }
+    // Make sure that the parameter input passed through to the tail call
+    // corresponds to the correct stack slot.
     size_t param_index = ParameterIndexOf(input->op());
-    if (param_index != stack_parameter) {
+    if (param_index != current_input - 1) {
       return false;
     }
-    ++stack_parameter;
     ++current_input;
     ++other_input;
   }

test/unittests/unittests.gyp

@@ -66,6 +66,7 @@
         'compiler/js-operator-unittest.cc',
         'compiler/js-typed-lowering-unittest.cc',
         'compiler/js-type-feedback-unittest.cc',
+        'compiler/linkage-tail-call-unittest.cc',
         'compiler/liveness-analyzer-unittest.cc',
         'compiler/load-elimination-unittest.cc',
         'compiler/loop-peeling-unittest.cc',