Optimizing: Better invoke-static/-direct dispatch.

Add framework for different types of loading ArtMethod*
and code pointer retrieval. Implement invoke-static and
invoke-direct calls the same way as Quick. Document the
dispatch kinds in HInvokeStaticOrDirect's new enumerations
MethodLoadKind and CodePtrLocation.

PC-relative loads from dex cache arrays are used only for
x86-64 and arm64. The implementation for other architectures
will be done in separate CLs.

Change-Id: I468ca4d422dbd14748e1ba6b45289f0d31734d94
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 091a3e5..96ef863 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -18,6 +18,7 @@
 
 #include "art_method.h"
 #include "code_generator_utils.h"
+#include "compiled_method.h"
 #include "entrypoints/quick/quick_entrypoints.h"
 #include "entrypoints/quick/quick_entrypoints_enum.h"
 #include "gc/accounting/card_table.h"
@@ -450,7 +451,9 @@
       location_builder_(graph, this),
       instruction_visitor_(graph, this),
       move_resolver_(graph->GetArena(), this),
-      isa_features_(isa_features) {
+      isa_features_(isa_features),
+      method_patches_(graph->GetArena()->Adapter()),
+      relative_call_patches_(graph->GetArena()->Adapter()) {
   // Use a fake return address register to mimic Quick.
   AddAllocatedRegister(Location::RegisterLocation(kFakeReturnRegister));
 }
@@ -3521,50 +3524,94 @@
 }
 
 
-void CodeGeneratorX86::GenerateStaticOrDirectCall(HInvokeStaticOrDirect* invoke,
-                                                  Location temp) {
-  // TODO: Implement all kinds of calls:
-  // 1) boot -> boot
-  // 2) app -> boot
-  // 3) app -> app
-  //
-  // Currently we implement the app -> app logic, which looks up in the resolve cache.
-
-  if (invoke->IsStringInit()) {
-    // temp = thread->string_init_entrypoint
-    Register reg = temp.AsRegister<Register>();
-    __ fs()->movl(reg, Address::Absolute(invoke->GetStringInitOffset()));
-    // (temp + offset_of_quick_compiled_code)()
-    __ call(Address(
-        reg, ArtMethod::EntryPointFromQuickCompiledCodeOffset(kX86WordSize).Int32Value()));
-  } else if (invoke->IsRecursive()) {
-    __ call(GetFrameEntryLabel());
-  } else {
-    Location current_method = invoke->GetLocations()->InAt(invoke->GetCurrentMethodInputIndex());
-
-    Register method_reg;
-    Register reg = temp.AsRegister<Register>();
-    if (current_method.IsRegister()) {
-      method_reg = current_method.AsRegister<Register>();
-    } else {
-      DCHECK(IsBaseline() || invoke->GetLocations()->Intrinsified());
-      DCHECK(!current_method.IsValid());
-      method_reg = reg;
-      __ movl(reg, Address(ESP, kCurrentMethodStackOffset));
+void CodeGeneratorX86::GenerateStaticOrDirectCall(HInvokeStaticOrDirect* invoke, Location temp) {
+  switch (invoke->GetMethodLoadKind()) {
+    case HInvokeStaticOrDirect::MethodLoadKind::kStringInit:
+      // temp = thread->string_init_entrypoint
+      __ fs()->movl(temp.AsRegister<Register>(), Address::Absolute(invoke->GetStringInitOffset()));
+      break;
+    case HInvokeStaticOrDirect::MethodLoadKind::kRecursive:
+      // Nothing to do.
+      break;
+    case HInvokeStaticOrDirect::MethodLoadKind::kDirectAddress:
+      __ movl(temp.AsRegister<Register>(), Immediate(invoke->GetMethodAddress()));
+      break;
+    case HInvokeStaticOrDirect::MethodLoadKind::kDirectAddressWithFixup:
+      __ movl(temp.AsRegister<Register>(), Immediate(0));  // Placeholder.
+      method_patches_.emplace_back(invoke->GetTargetMethod());
+      __ Bind(&method_patches_.back().label);  // Bind the label at the end of the "movl" insn.
+      break;
+    case HInvokeStaticOrDirect::MethodLoadKind::kDexCachePcRelative:
+      // TODO: Implement this type. For the moment, we fall back to kDexCacheViaMethod.
+      FALLTHROUGH_INTENDED;
+    case HInvokeStaticOrDirect::MethodLoadKind::kDexCacheViaMethod: {
+      Location current_method = invoke->GetLocations()->InAt(invoke->GetCurrentMethodInputIndex());
+      Register method_reg;
+      Register reg = temp.AsRegister<Register>();
+      if (current_method.IsRegister()) {
+        method_reg = current_method.AsRegister<Register>();
+      } else {
+        DCHECK(IsBaseline() || invoke->GetLocations()->Intrinsified());
+        DCHECK(!current_method.IsValid());
+        method_reg = reg;
+        __ movl(reg, Address(ESP, kCurrentMethodStackOffset));
+      }
+      // temp = temp->dex_cache_resolved_methods_;
+      __ movl(reg, Address(method_reg, ArtMethod::DexCacheResolvedMethodsOffset().Int32Value()));
+      // temp = temp[index_in_cache]
+      uint32_t index_in_cache = invoke->GetTargetMethod().dex_method_index;
+      __ movl(reg, Address(reg, CodeGenerator::GetCachePointerOffset(index_in_cache)));
+      break;
     }
-    // temp = temp->dex_cache_resolved_methods_;
-    __ movl(reg, Address(method_reg, ArtMethod::DexCacheResolvedMethodsOffset().Int32Value()));
-    // temp = temp[index_in_cache]
-    __ movl(reg, Address(reg,
-                         CodeGenerator::GetCachePointerOffset(invoke->GetDexMethodIndex())));
-    // (temp + offset_of_quick_compiled_code)()
-    __ call(Address(reg,
-        ArtMethod::EntryPointFromQuickCompiledCodeOffset(kX86WordSize).Int32Value()));
+  }
+
+  switch (invoke->GetCodePtrLocation()) {
+    case HInvokeStaticOrDirect::CodePtrLocation::kCallSelf:
+      __ call(GetFrameEntryLabel());
+      break;
+    case HInvokeStaticOrDirect::CodePtrLocation::kCallPCRelative: {
+      relative_call_patches_.emplace_back(invoke->GetTargetMethod());
+      Label* label = &relative_call_patches_.back().label;
+      __ call(label);  // Bind to the patch label, override at link time.
+      __ Bind(label);  // Bind the label at the end of the "call" insn.
+      break;
+    }
+    case HInvokeStaticOrDirect::CodePtrLocation::kCallDirectWithFixup:
+    case HInvokeStaticOrDirect::CodePtrLocation::kCallDirect:
+      // For direct code, we actually prefer to call via the code pointer from ArtMethod*.
+      // (Though the direct CALL ptr16:32 is available for consideration).
+      FALLTHROUGH_INTENDED;
+    case HInvokeStaticOrDirect::CodePtrLocation::kCallArtMethod:
+      // (temp + offset_of_quick_compiled_code)()
+      __ call(Address(temp.AsRegister<Register>(), ArtMethod::EntryPointFromQuickCompiledCodeOffset(
+          kX86WordSize).Int32Value()));
+      break;
   }
 
   DCHECK(!IsLeafMethod());
 }
 
+void CodeGeneratorX86::EmitLinkerPatches(ArenaVector<LinkerPatch>* linker_patches) {
+  DCHECK(linker_patches->empty());
+  linker_patches->reserve(method_patches_.size() + relative_call_patches_.size());
+  for (const MethodPatchInfo<Label>& info : method_patches_) {
+    // The label points to the end of the "movl" insn but the literal offset for method
+    // patch x86 needs to point to the embedded constant which occupies the last 4 bytes.
+    uint32_t literal_offset = info.label.Position() - 4;
+    linker_patches->push_back(LinkerPatch::MethodPatch(literal_offset,
+                                                       info.target_method.dex_file,
+                                                       info.target_method.dex_method_index));
+  }
+  for (const MethodPatchInfo<Label>& info : relative_call_patches_) {
+    // The label points to the end of the "call" insn but the literal offset for method
+    // patch x86 needs to point to the embedded constant which occupies the last 4 bytes.
+    uint32_t literal_offset = info.label.Position() - 4;
+    linker_patches->push_back(LinkerPatch::RelativeCodePatch(literal_offset,
+                                                             info.target_method.dex_file,
+                                                             info.target_method.dex_method_index));
+  }
+}
+
 void CodeGeneratorX86::MarkGCCard(Register temp,
                                   Register card,
                                   Register object,