[wasm][cleanup] Fix NumLocals function

Should be num_locals, and const.

R=titzer@chromium.org

Bug: v8:8562
Change-Id: I60889c9912ef95d344ede4d7755028116feee47e
Reviewed-on: https://chromium-review.googlesource.com/c/1373784Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58197}

src/wasm/baseline/liftoff-compiler.cc

@@ -230,7 +230,7 @@ class LiftoffCompiler {
   }
 
   void StartFunction(FullDecoder* decoder) {
-    int num_locals = decoder->NumLocals();
+    int num_locals = decoder->num_locals();
     __ set_num_locals(num_locals);
     for (int i = 0; i < num_locals; ++i) {
       __ set_local_type(i, decoder->GetLocalType(i));

src/wasm/function-body-decoder-impl.h

@@ -1492,7 +1492,7 @@ class WasmFullDecoder : public WasmDecoder<validate> {
 
   inline Zone* zone() const { return zone_; }
 
-  inline uint32_t NumLocals() {
+  inline uint32_t num_locals() const {
     return static_cast<uint32_t>(local_type_vec_.size());
   }
 

src/wasm/graph-builder-interface.cc

@@ -87,7 +87,7 @@ class WasmGraphBuildingInterface {
   void StartFunction(FullDecoder* decoder) {
     SsaEnv* ssa_env =
         reinterpret_cast<SsaEnv*>(decoder->zone()->New(sizeof(SsaEnv)));
-    uint32_t num_locals = decoder->NumLocals();
+    uint32_t num_locals = decoder->num_locals();
     uint32_t env_count = num_locals;
     size_t size = sizeof(TFNode*) * env_count;
     ssa_env->state = SsaEnv::kReached;
@@ -702,7 +702,7 @@ class WasmGraphBuildingInterface {
           to->effect = builder_->EffectPhi(2, effects, merge);
         }
         // Merge SSA values.
-        for (int i = decoder->NumLocals() - 1; i >= 0; i--) {
+        for (int i = decoder->num_locals() - 1; i >= 0; i--) {
           TFNode* a = to->locals[i];
           TFNode* b = from->locals[i];
           if (a != b) {
@@ -724,7 +724,7 @@ class WasmGraphBuildingInterface {
         to->effect = builder_->CreateOrMergeIntoEffectPhi(merge, to->effect,
                                                           from->effect);
         // Merge locals.
-        for (int i = decoder->NumLocals() - 1; i >= 0; i--) {
+        for (int i = decoder->num_locals() - 1; i >= 0; i--) {
           to->locals[i] = builder_->CreateOrMergeIntoPhi(
               ValueTypes::MachineRepresentationFor(decoder->GetLocalType(i)),
               merge, to->locals[i], from->locals[i]);
@@ -754,7 +754,7 @@ class WasmGraphBuildingInterface {
     if (assigned != nullptr) {
       // Only introduce phis for variables assigned in this loop.
       int instance_cache_index = decoder->total_locals();
-      for (int i = decoder->NumLocals() - 1; i >= 0; i--) {
+      for (int i = decoder->num_locals() - 1; i >= 0; i--) {
         if (!assigned->Contains(i)) continue;
         env->locals[i] = builder_->Phi(decoder->GetLocalType(i), 1,
                                        &env->locals[i], env->control);
@@ -772,7 +772,7 @@ class WasmGraphBuildingInterface {
     }
 
     // Conservatively introduce phis for all local variables.
-    for (int i = decoder->NumLocals() - 1; i >= 0; i--) {
+    for (int i = decoder->num_locals() - 1; i >= 0; i--) {
       env->locals[i] = builder_->Phi(decoder->GetLocalType(i), 1,
                                      &env->locals[i], env->control);
     }
@@ -791,7 +791,7 @@ class WasmGraphBuildingInterface {
     DCHECK_NOT_NULL(from);
     SsaEnv* result =
         reinterpret_cast<SsaEnv*>(decoder->zone()->New(sizeof(SsaEnv)));
-    size_t size = sizeof(TFNode*) * decoder->NumLocals();
+    size_t size = sizeof(TFNode*) * decoder->num_locals();
     result->control = from->control;
     result->effect = from->effect;