ART: Clean up patching data in codegens.

Reuse PatchInfo<> for additional architectures and make the
naming more consistent across architectures. Change the
DexFile reference to pointer in preparation for patching
references to the upcoming .data.bimg.rel.ro section.

Update obsolete comments; instead of referencing dex cache
arrays which were used in the past, reference the .bss and
the .data.bimg.rel.ro which shall be used in upcoming CLs.

Test: Rely on TreeHugger.
Change-Id: I03be4c4118918189e55c62105bb594500c6a42c1

1 files changed, 16 insertions, 14 deletions

diff --git a/compiler/optimizing/code_generator_arm_vixl.h b/compiler/optimizing/code_generator_arm_vixl.h
index 38570bb0fe..bbc715c59d 100644
--- a/compiler/optimizing/code_generator_arm_vixl.h
+++ b/compiler/optimizing/code_generator_arm_vixl.h
@@ -552,32 +552,34 @@ class CodeGeneratorARMVIXL : public CodeGenerator {
 
   void MoveFromReturnRegister(Location trg, DataType::Type type) OVERRIDE;
 
-  // The PcRelativePatchInfo is used for PC-relative addressing of dex cache arrays
-  // and boot image strings/types. The only difference is the interpretation of the
-  // offset_or_index. The PC-relative address is loaded with three instructions,
+  // The PcRelativePatchInfo is used for PC-relative addressing of methods/strings/types,
+  // whether through .data.bimg.rel.ro, .bss, or directly in the boot image.
+  //
+  // The PC-relative address is loaded with three instructions,
   // MOVW+MOVT to load the offset to base_reg and then ADD base_reg, PC. The offset
   // is calculated from the ADD's effective PC, i.e. PC+4 on Thumb2. Though we
   // currently emit these 3 instructions together, instruction scheduling could
   // split this sequence apart, so we keep separate labels for each of them.
   struct PcRelativePatchInfo {
-    PcRelativePatchInfo(const DexFile& dex_file, uint32_t off_or_idx)
+    PcRelativePatchInfo(const DexFile* dex_file, uint32_t off_or_idx)
         : target_dex_file(dex_file), offset_or_index(off_or_idx) { }
     PcRelativePatchInfo(PcRelativePatchInfo&& other) = default;
 
-    const DexFile& target_dex_file;
-    // Either the dex cache array element offset or the string/type index.
+    // Target dex file or null for .data.bmig.rel.ro patches.
+    const DexFile* target_dex_file;
+    // Either the boot image offset (to write to .data.bmig.rel.ro) or string/type/method index.
     uint32_t offset_or_index;
     vixl::aarch32::Label movw_label;
     vixl::aarch32::Label movt_label;
     vixl::aarch32::Label add_pc_label;
   };
 
-  PcRelativePatchInfo* NewPcRelativeMethodPatch(MethodReference target_method);
+  PcRelativePatchInfo* NewBootImageMethodPatch(MethodReference target_method);
   PcRelativePatchInfo* NewMethodBssEntryPatch(MethodReference target_method);
-  PcRelativePatchInfo* NewPcRelativeTypePatch(const DexFile& dex_file, dex::TypeIndex type_index);
+  PcRelativePatchInfo* NewBootImageTypePatch(const DexFile& dex_file, dex::TypeIndex type_index);
   PcRelativePatchInfo* NewTypeBssEntryPatch(const DexFile& dex_file, dex::TypeIndex type_index);
-  PcRelativePatchInfo* NewPcRelativeStringPatch(const DexFile& dex_file,
-                                                dex::StringIndex string_index);
+  PcRelativePatchInfo* NewBootImageStringPatch(const DexFile& dex_file,
+                                               dex::StringIndex string_index);
   PcRelativePatchInfo* NewStringBssEntryPatch(const DexFile& dex_file,
                                               dex::StringIndex string_index);
 
@@ -774,7 +776,7 @@ class CodeGeneratorARMVIXL : public CodeGenerator {
   };
 
   VIXLUInt32Literal* DeduplicateUint32Literal(uint32_t value, Uint32ToLiteralMap* map);
-  PcRelativePatchInfo* NewPcRelativePatch(const DexFile& dex_file,
+  PcRelativePatchInfo* NewPcRelativePatch(const DexFile* dex_file,
                                           uint32_t offset_or_index,
                                           ArenaDeque<PcRelativePatchInfo>* patches);
   template <linker::LinkerPatch (*Factory)(size_t, const DexFile*, uint32_t, uint32_t)>
@@ -797,15 +799,15 @@ class CodeGeneratorARMVIXL : public CodeGenerator {
   // Deduplication map for 32-bit literals, used for non-patchable boot image addresses.
   Uint32ToLiteralMap uint32_literals_;
   // PC-relative method patch info for kBootImageLinkTimePcRelative.
-  ArenaDeque<PcRelativePatchInfo> pc_relative_method_patches_;
+  ArenaDeque<PcRelativePatchInfo> boot_image_method_patches_;
   // PC-relative method patch info for kBssEntry.
   ArenaDeque<PcRelativePatchInfo> method_bss_entry_patches_;
   // PC-relative type patch info for kBootImageLinkTimePcRelative.
-  ArenaDeque<PcRelativePatchInfo> pc_relative_type_patches_;
+  ArenaDeque<PcRelativePatchInfo> boot_image_type_patches_;
   // PC-relative type patch info for kBssEntry.
   ArenaDeque<PcRelativePatchInfo> type_bss_entry_patches_;
   // PC-relative String patch info; type depends on configuration (intern table or boot image PIC).
-  ArenaDeque<PcRelativePatchInfo> pc_relative_string_patches_;
+  ArenaDeque<PcRelativePatchInfo> boot_image_string_patches_;
   // PC-relative String patch info for kBssEntry.
   ArenaDeque<PcRelativePatchInfo> string_bss_entry_patches_;
   // Baker read barrier patch info.