Global Value Numbering.
Implement the Global Value Numbering for optimization
purposes. Use it for the null check and range check
elimination as the LVN used to do.
The order of evaluation of basic blocks needs improving as
we currently fail to recognize some obviously identical
values in methods with more than one loop. (There are three
disabled tests that check this. This is just a missed
optimization, not a correctness issue.)
Change-Id: I0d0ce16b2495b5a3b17ad1b2b32931cd69f5a25a
diff --git a/compiler/dex/mir_graph.h b/compiler/dex/mir_graph.h
index f812165..d097328 100644
--- a/compiler/dex/mir_graph.h
+++ b/compiler/dex/mir_graph.h
@@ -32,6 +32,8 @@
namespace art {
+class GlobalValueNumbering;
+
enum InstructionAnalysisAttributePos {
kUninterestingOp = 0,
kArithmeticOp,
@@ -899,6 +901,9 @@
bool EliminateClassInitChecksGate();
bool EliminateClassInitChecks(BasicBlock* bb);
void EliminateClassInitChecksEnd();
+ bool ApplyGlobalValueNumberingGate();
+ bool ApplyGlobalValueNumbering(BasicBlock* bb);
+ void ApplyGlobalValueNumberingEnd();
/*
* Type inference handling helpers. Because Dalvik's bytecode is not fully typed,
* we have to do some work to figure out the sreg type. For some operations it is
@@ -1123,6 +1128,7 @@
uint16_t* temp_insn_data_;
uint32_t temp_bit_vector_size_;
ArenaBitVector* temp_bit_vector_;
+ std::unique_ptr<GlobalValueNumbering> temp_gvn_;
static const int kInvalidEntry = -1;
GrowableArray<BasicBlock*> block_list_;
ArenaBitVector* try_block_addr_;
@@ -1159,6 +1165,7 @@
GrowableArray<BasicBlock*> gen_suspend_test_list_; // List of blocks containing suspend tests
friend class ClassInitCheckEliminationTest;
+ friend class GlobalValueNumberingTest;
friend class LocalValueNumberingTest;
};