Revert "Use trampolines for calls to helpers"
This reverts commit 754ddad084ccb610d0cf486f6131bdc69bae5bc6.
Change-Id: Icd979adee1d8d781b40a5e75daf3719444cb72e8
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index 8bf3b04..a241d51 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -24,8 +24,6 @@
#include <unistd.h>
#include <utility>
-#include "arch/arm/final_relocations_arm.h"
-#include "base/hex_dump.h"
#include "base/stl_util.h"
#include "base/timing_logger.h"
#include "class_linker.h"
@@ -508,7 +506,6 @@
UniquePtr<ThreadPool> thread_pool(new ThreadPool("Compiler driver thread pool", thread_count_ - 1));
PreCompile(class_loader, dex_files, thread_pool.get(), timings);
Compile(class_loader, dex_files, thread_pool.get(), timings);
- PostCompile();
if (dump_stats_) {
stats_->Dump();
}
@@ -620,10 +617,6 @@
UpdateImageClasses(timings);
}
-void CompilerDriver::PostCompile() {
- BuildEntrypointTrampolineCode();
-}
-
bool CompilerDriver::IsImageClass(const char* descriptor) const {
if (!IsImage()) {
return true;
@@ -1247,25 +1240,6 @@
return result;
}
-uint32_t CompilerDriver::AddEntrypointTrampoline(uint32_t entrypoint) {
- return entrypoint_trampolines_.AddEntrypoint(Thread::Current(), entrypoint);
-}
-
-
-void CompilerDriver::BuildEntrypointTrampolineCode() {
- const auto& table = entrypoint_trampolines_.GetTrampolineTable();
- for (uint32_t offset : table) {
- switch (instruction_set_) {
- case kThumb2:
- BuildArmEntrypointTrampolineCall(ThreadOffset<4>(offset));
- break;
- default:
- UNIMPLEMENTED(FATAL) << "No entrypoint trampolines for this architecture";
- }
- }
-}
-
-
void CompilerDriver::AddCodePatch(const DexFile* dex_file,
uint16_t referrer_class_def_idx,
uint32_t referrer_method_idx,
@@ -2176,17 +2150,4 @@
}
return !compile;
}
-
-FinalEntrypointRelocationSet* CompilerDriver::AllocateFinalEntrypointRelocationSet(
- CompilationUnit* cu) const {
- switch (instruction_set_) {
- case kArm:
- case kThumb2:
- return new FinalEntrypointRelocationSetArm(this);
- default:
- UNIMPLEMENTED(FATAL) << "Cannot allocate FinalEntrypointRelocationSet for non-ARM";
- return nullptr;
- }
-}
-
} // namespace art
diff --git a/compiler/driver/compiler_driver.h b/compiler/driver/compiler_driver.h
index 6df5d0c..802f859 100644
--- a/compiler/driver/compiler_driver.h
+++ b/compiler/driver/compiler_driver.h
@@ -634,112 +634,6 @@
// Should the compiler run on this method given profile information?
bool SkipCompilation(const std::string& method_name);
- // Entrypoint trampolines.
- //
- // The idea here is that we can save code size by collecting the branches
- // to the entrypoints (helper functions called by the generated code) into a
- // table and then branching relative to that table from the code. On ARM 32 this
- // will save 2 bytes per call. Only the entrypoints used by the program (the whole
- // program - these are global) are in this table and are in no particular order.
- //
- // The trampolines will be placed right at the start of the .text section in the file
- // and will consist of a table of instructions, each of which will branch relative to
- // the thread register (r9 on ARM) to an entrypoint. On ARM this would look like:
- //
- // trampolines:
- // 1: ldr pc, [r9, #40]
- // 2: ldr pc, [r9, #8]
- // ...
- //
- // Then a call to an entrypoint would be an immediate BL instruction to the appropriate
- // label (1 or 2 in the above example). Because the entrypoint table has the lower bit
- // of the address already set, the ldr pc will switch from ARM to Thumb for the entrypoint as
- // necessary.
- //
- // On ARM, the range of a BL instruction is +-32M to this is more than enough for an
- // immediate BL instruction in the generated code.
- //
- // The actual address of the trampoline for a particular entrypoint is not known until
- // the OAT file is written and we know the addresses of all the branch instructions in
- // the program. At this point we can rewrite the BL instruction to have the correct relative
- // offset.
- class EntrypointTrampolines {
- public:
- EntrypointTrampolines() : current_offset_(0), lock_("Entrypoint Trampolines") {}
- ~EntrypointTrampolines() {}
-
- // Add a trampoline and return the offset added. If it already exists
- // return the offset it was added at previously.
- uint32_t AddEntrypoint(Thread* self, uint32_t ep) LOCKS_EXCLUDED(lock_) {
- MutexLock mu(self, lock_);
- Trampolines::iterator tramp = trampolines_.find(ep);
- if (tramp == trampolines_.end()) {
- trampolines_[ep] = current_offset_;
- trampoline_table_.push_back(ep);
- LOG(DEBUG) << "adding new trampoline for " << ep << " at offset " << current_offset_;
- return current_offset_++;
- } else {
- return tramp->second;
- }
- }
-
- const std::vector<uint32_t>& GetTrampolineTable() const {
- return trampoline_table_;
- }
-
- uint32_t GetTrampolineTableSize() const {
- return current_offset_;
- }
-
- private:
- uint32_t current_offset_;
- // Mapping of entrypoint offset vs offset into trampoline table.
- typedef std::map<uint32_t, uint32_t> Trampolines;
- Trampolines trampolines_ GUARDED_BY(lock_);
-
- // Table of all registered offsets in order of registration.
- std::vector<uint32_t> trampoline_table_;
- Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
- };
-
- uint32_t AddEntrypointTrampoline(uint32_t entrypoint);
-
- const std::vector<uint32_t>& GetEntrypointTrampolineTable() const {
- return entrypoint_trampolines_.GetTrampolineTable();
- }
-
- uint32_t GetEntrypointTrampolineTableSize() const {
- uint32_t size = entrypoint_trampolines_.GetTrampolineTableSize();
- if (instruction_set_ == kThumb2) {
- return size * 4;
- }
- return size;
- }
-
- // Get the maximum offset between entrypoint trampoline islands. Different architectures
- // have limitations on the max offset for a call instruction. This function is used
- // to determine when we need to generate a new trampoline island in the output to keep
- // subsequent calls in range.
- size_t GetMaxEntrypointTrampolineOffset() const {
- if (instruction_set_ == kThumb2) {
- // On Thumb2, the max range of a BL instruction is 16MB. Give it a little wiggle room.
- return 15*MB;
- }
- // Returning 0 means we won't generate a trampoline island.
- return 0;
- }
-
- void BuildEntrypointTrampolineCode();
-
- // Architecture specific Entrypoint trampoline builder.
- void BuildArmEntrypointTrampolineCall(ThreadOffset<4> offset);
-
- const std::vector<uint8_t>& GetEntrypointTrampolineTableCode() const {
- return entrypoint_trampoline_code_;
- }
-
- FinalEntrypointRelocationSet* AllocateFinalEntrypointRelocationSet(CompilationUnit* cu) const;
-
private:
// These flags are internal to CompilerDriver for collecting INVOKE resolution statistics.
// The only external contract is that unresolved method has flags 0 and resolved non-0.
@@ -777,7 +671,6 @@
LOCKS_EXCLUDED(Locks::mutator_lock_);
void LoadImageClasses(TimingLogger* timings);
- void PostCompile() LOCKS_EXCLUDED(Locks::mutator_lock_);
// Attempt to resolve all type, methods, fields, and strings
// referenced from code in the dex file following PathClassLoader
@@ -938,10 +831,6 @@
DedupeSet<std::vector<uint8_t>, size_t, DedupeHashFunc, 4> dedupe_gc_map_;
DedupeSet<std::vector<uint8_t>, size_t, DedupeHashFunc, 4> dedupe_cfi_info_;
- EntrypointTrampolines entrypoint_trampolines_;
-
- std::vector<uint8_t> entrypoint_trampoline_code_;
-
DISALLOW_COPY_AND_ASSIGN(CompilerDriver);
};
diff --git a/compiler/driver/compiler_options.h b/compiler/driver/compiler_options.h
index 52248a6..20c6bc8 100644
--- a/compiler/driver/compiler_options.h
+++ b/compiler/driver/compiler_options.h
@@ -50,8 +50,7 @@
small_method_threshold_(kDefaultSmallMethodThreshold),
tiny_method_threshold_(kDefaultTinyMethodThreshold),
num_dex_methods_threshold_(kDefaultNumDexMethodsThreshold),
- generate_gdb_information_(false),
- generate_helper_trampolines_(false)
+ generate_gdb_information_(false)
#ifdef ART_SEA_IR_MODE
, sea_ir_mode_(false)
#endif
@@ -63,8 +62,7 @@
size_t small_method_threshold,
size_t tiny_method_threshold,
size_t num_dex_methods_threshold,
- bool generate_gdb_information,
- bool generate_helper_trampolines
+ bool generate_gdb_information
#ifdef ART_SEA_IR_MODE
, bool sea_ir_mode
#endif
@@ -75,8 +73,7 @@
small_method_threshold_(small_method_threshold),
tiny_method_threshold_(tiny_method_threshold),
num_dex_methods_threshold_(num_dex_methods_threshold),
- generate_gdb_information_(generate_gdb_information),
- generate_helper_trampolines_(generate_helper_trampolines)
+ generate_gdb_information_(generate_gdb_information)
#ifdef ART_SEA_IR_MODE
, sea_ir_mode_(sea_ir_mode)
#endif
@@ -143,10 +140,6 @@
return generate_gdb_information_;
}
- bool GenerateHelperTrampolines() const {
- return generate_helper_trampolines_;
- }
-
private:
CompilerFilter compiler_filter_;
size_t huge_method_threshold_;
@@ -155,7 +148,6 @@
size_t tiny_method_threshold_;
size_t num_dex_methods_threshold_;
bool generate_gdb_information_;
- bool generate_helper_trampolines_;
#ifdef ART_SEA_IR_MODE
bool sea_ir_mode_;