From 7c3560f2ce0ec9484004d05a94bfaa6e02f5a96a Mon Sep 17 00:00:00 2001 From: Nicolas Geoffray Date: Wed, 4 Jun 2014 12:12:08 +0100 Subject: Fix a bug in SSA construction. If a join block does not have an incoming value for a local from a predecessor block, we should not create a phi. The verifier has made sure the local is updated before any following reads after this block. Change-Id: Id2785efc73c9fb3224826fff2f4b4ad215905ff4 --- compiler/optimizing/ssa_test.cc | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'compiler/optimizing/ssa_test.cc') diff --git a/compiler/optimizing/ssa_test.cc b/compiler/optimizing/ssa_test.cc index d10461980d..485ea279ad 100644 --- a/compiler/optimizing/ssa_test.cc +++ b/compiler/optimizing/ssa_test.cc @@ -459,4 +459,34 @@ TEST(SsaTest, DeadLocal) { TestCode(data, expected); } +TEST(SsaTest, LocalInIf) { + // Test that we do not create a phi in the join block when one predecessor + // does not update the local. + const char* expected = + "BasicBlock 0, succ: 1\n" + " 0: IntConstant 0 [3, 3]\n" + " 1: IntConstant 4\n" + " 2: Goto\n" + "BasicBlock 1, pred: 0, succ: 2, 5\n" + " 3: Equal(0, 0) [4]\n" + " 4: If(3)\n" + "BasicBlock 2, pred: 1, succ: 3\n" + " 5: Goto\n" + "BasicBlock 3, pred: 2, 5, succ: 4\n" + " 6: ReturnVoid\n" + "BasicBlock 4, pred: 3\n" + " 7: Exit\n" + // Synthesized block to avoid critical edge. + "BasicBlock 5, pred: 1, succ: 3\n" + " 8: Goto\n"; + + const uint16_t data[] = TWO_REGISTERS_CODE_ITEM( + Instruction::CONST_4 | 0 | 0, + Instruction::IF_EQ, 3, + Instruction::CONST_4 | 4 << 12 | 1 << 8, + Instruction::RETURN_VOID); + + TestCode(data, expected); +} + } // namespace art -- cgit v1.2.3-59-g8ed1b