remove most uses of Isolate::Current in arch specific files

src/x64/ic-x64.cc

Index: src/x64/ic-x64.cc
diff --git a/src/x64/ic-x64.cc b/src/x64/ic-x64.cc
index 84a47d6ac42865f1e2b08452f94ee14cfb56aba4..4a7c68a53ca4db309ef6570819df88f3fa94aaa3 100644
--- a/src/x64/ic-x64.cc
+++ b/src/x64/ic-x64.cc
@@ -822,8 +822,8 @@ void CallICBase::GenerateMonomorphicCacheProbe(MacroAssembler* masm,
                                          extra_state,
                                          Code::NORMAL,
                                          argc);
-  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rdx, rcx, rbx,
-                                                  rax);
+  masm->isolate()->stub_cache()->GenerateProbe(
+      masm, flags, rdx, rcx, rbx, rax);
 
   // If the stub cache probing failed, the receiver might be a value.
   // For value objects, we use the map of the prototype objects for
@@ -859,8 +859,8 @@ void CallICBase::GenerateMonomorphicCacheProbe(MacroAssembler* masm,
 
   // Probe the stub cache for the value object.
   __ bind(&probe);
-  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rdx, rcx, rbx,
-                                                  no_reg);
+  masm->isolate()->stub_cache()->GenerateProbe(
+      masm, flags, rdx, rcx, rbx, no_reg);
 
   __ bind(&miss);
 }
@@ -1332,7 +1332,7 @@ void LoadIC::GenerateMegamorphic(MacroAssembler* masm) {
   Code::Flags flags = Code::ComputeFlags(
       Code::STUB, MONOMORPHIC, Code::kNoExtraICState,
       Code::NORMAL, Code::LOAD_IC);
-  Isolate::Current()->stub_cache()->GenerateProbe(
+  masm->isolate()->stub_cache()->GenerateProbe(
       masm, flags, rax, rcx, rbx, rdx);
 
   GenerateMiss(masm);
@@ -1453,8 +1453,8 @@ void StoreIC::GenerateMegamorphic(MacroAssembler* masm,
   Code::Flags flags = Code::ComputeFlags(
       Code::STUB, MONOMORPHIC, strict_mode,
       Code::NORMAL, Code::STORE_IC);
-  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rdx, rcx, rbx,
-                                                  no_reg);
+  masm->isolate()->stub_cache()->GenerateProbe(
+      masm, flags, rdx, rcx, rbx, no_reg);
 
   // Cache miss: Jump to runtime.
   GenerateMiss(masm);