ART: Fix left-shift of negative numbers

Shifting negative numbers is undefined.

Change-Id: I0c32a3fcf372eae74507a5f2383edbfaf5c6830c

diff --git a/compiler/dex/local_value_numbering_test.cc b/compiler/dex/local_value_numbering_test.cc
index bd00690..f98969e 100644 (file)
--- a/compiler/dex/local_value_numbering_test.cc
+++ b/compiler/dex/local_value_numbering_test.cc
@@ -797,6 +797,10 @@ TEST_F(LocalValueNumberingTest, DivZeroCheck) {
   }
 }
 
+static constexpr int64_t shift_minus_1(size_t by) {
+  return static_cast<int64_t>(static_cast<uint64_t>(INT64_C(-1)) << by);
+}
+
 TEST_F(LocalValueNumberingTest, ConstWide) {
   static const MIRDef mirs[] = {
       // Core reg constants.
@@ -804,45 +808,45 @@ TEST_F(LocalValueNumberingTest, ConstWide) {
       DEF_CONST(Instruction::CONST_WIDE_16, 2u, 1),
       DEF_CONST(Instruction::CONST_WIDE_16, 4u, -1),
       DEF_CONST(Instruction::CONST_WIDE_32, 6u, 1 << 16),
-      DEF_CONST(Instruction::CONST_WIDE_32, 8u, -1 << 16),
+      DEF_CONST(Instruction::CONST_WIDE_32, 8u, shift_minus_1(16)),
       DEF_CONST(Instruction::CONST_WIDE_32, 10u, (1 << 16) + 1),
       DEF_CONST(Instruction::CONST_WIDE_32, 12u, (1 << 16) - 1),
       DEF_CONST(Instruction::CONST_WIDE_32, 14u, -(1 << 16) + 1),
       DEF_CONST(Instruction::CONST_WIDE_32, 16u, -(1 << 16) - 1),
       DEF_CONST(Instruction::CONST_WIDE, 18u, INT64_C(1) << 32),
-      DEF_CONST(Instruction::CONST_WIDE, 20u, INT64_C(-1) << 32),
+      DEF_CONST(Instruction::CONST_WIDE, 20u, shift_minus_1(32)),
       DEF_CONST(Instruction::CONST_WIDE, 22u, (INT64_C(1) << 32) + 1),
       DEF_CONST(Instruction::CONST_WIDE, 24u, (INT64_C(1) << 32) - 1),
-      DEF_CONST(Instruction::CONST_WIDE, 26u, (INT64_C(-1) << 32) + 1),
-      DEF_CONST(Instruction::CONST_WIDE, 28u, (INT64_C(-1) << 32) - 1),
+      DEF_CONST(Instruction::CONST_WIDE, 26u, shift_minus_1(32) + 1),
+      DEF_CONST(Instruction::CONST_WIDE, 28u, shift_minus_1(32) - 1),
       DEF_CONST(Instruction::CONST_WIDE_HIGH16, 30u, 1),       // Effectively 1 << 48.
       DEF_CONST(Instruction::CONST_WIDE_HIGH16, 32u, 0xffff),  // Effectively -1 << 48.
       DEF_CONST(Instruction::CONST_WIDE, 34u, (INT64_C(1) << 48) + 1),
       DEF_CONST(Instruction::CONST_WIDE, 36u, (INT64_C(1) << 48) - 1),
-      DEF_CONST(Instruction::CONST_WIDE, 38u, (INT64_C(-1) << 48) + 1),
-      DEF_CONST(Instruction::CONST_WIDE, 40u, (INT64_C(-1) << 48) - 1),
+      DEF_CONST(Instruction::CONST_WIDE, 38u, shift_minus_1(48) + 1),
+      DEF_CONST(Instruction::CONST_WIDE, 40u, shift_minus_1(48) - 1),
       // FP reg constants.
       DEF_CONST(Instruction::CONST_WIDE_16, 42u, 0),
       DEF_CONST(Instruction::CONST_WIDE_16, 44u, 1),
       DEF_CONST(Instruction::CONST_WIDE_16, 46u, -1),
       DEF_CONST(Instruction::CONST_WIDE_32, 48u, 1 << 16),
-      DEF_CONST(Instruction::CONST_WIDE_32, 50u, -1 << 16),
+      DEF_CONST(Instruction::CONST_WIDE_32, 50u, shift_minus_1(16)),
       DEF_CONST(Instruction::CONST_WIDE_32, 52u, (1 << 16) + 1),
       DEF_CONST(Instruction::CONST_WIDE_32, 54u, (1 << 16) - 1),
       DEF_CONST(Instruction::CONST_WIDE_32, 56u, -(1 << 16) + 1),
       DEF_CONST(Instruction::CONST_WIDE_32, 58u, -(1 << 16) - 1),
       DEF_CONST(Instruction::CONST_WIDE, 60u, INT64_C(1) << 32),
-      DEF_CONST(Instruction::CONST_WIDE, 62u, INT64_C(-1) << 32),
+      DEF_CONST(Instruction::CONST_WIDE, 62u, shift_minus_1(32)),
       DEF_CONST(Instruction::CONST_WIDE, 64u, (INT64_C(1) << 32) + 1),
       DEF_CONST(Instruction::CONST_WIDE, 66u, (INT64_C(1) << 32) - 1),
-      DEF_CONST(Instruction::CONST_WIDE, 68u, (INT64_C(-1) << 32) + 1),
-      DEF_CONST(Instruction::CONST_WIDE, 70u, (INT64_C(-1) << 32) - 1),
+      DEF_CONST(Instruction::CONST_WIDE, 68u, shift_minus_1(32) + 1),
+      DEF_CONST(Instruction::CONST_WIDE, 70u, shift_minus_1(32) - 1),
       DEF_CONST(Instruction::CONST_WIDE_HIGH16, 72u, 1),       // Effectively 1 << 48.
       DEF_CONST(Instruction::CONST_WIDE_HIGH16, 74u, 0xffff),  // Effectively -1 << 48.
       DEF_CONST(Instruction::CONST_WIDE, 76u, (INT64_C(1) << 48) + 1),
       DEF_CONST(Instruction::CONST_WIDE, 78u, (INT64_C(1) << 48) - 1),
-      DEF_CONST(Instruction::CONST_WIDE, 80u, (INT64_C(-1) << 48) + 1),
-      DEF_CONST(Instruction::CONST_WIDE, 82u, (INT64_C(-1) << 48) - 1),
+      DEF_CONST(Instruction::CONST_WIDE, 80u, shift_minus_1(48) + 1),
+      DEF_CONST(Instruction::CONST_WIDE, 82u, shift_minus_1(48) - 1),
   };
 
   PrepareMIRs(mirs);
@@ -868,7 +872,7 @@ TEST_F(LocalValueNumberingTest, Const) {
       DEF_CONST(Instruction::CONST_4, 1u, 1),
       DEF_CONST(Instruction::CONST_4, 2u, -1),
       DEF_CONST(Instruction::CONST_16, 3u, 1 << 4),
-      DEF_CONST(Instruction::CONST_16, 4u, -1 << 4),
+      DEF_CONST(Instruction::CONST_16, 4u, shift_minus_1(4)),
       DEF_CONST(Instruction::CONST_16, 5u, (1 << 4) + 1),
       DEF_CONST(Instruction::CONST_16, 6u, (1 << 4) - 1),
       DEF_CONST(Instruction::CONST_16, 7u, -(1 << 4) + 1),
@@ -877,14 +881,14 @@ TEST_F(LocalValueNumberingTest, Const) {
       DEF_CONST(Instruction::CONST_HIGH16, 10u, 0xffff),  // Effectively -1 << 16.
       DEF_CONST(Instruction::CONST, 11u, (1 << 16) + 1),
       DEF_CONST(Instruction::CONST, 12u, (1 << 16) - 1),
-      DEF_CONST(Instruction::CONST, 13u, (-1 << 16) + 1),
-      DEF_CONST(Instruction::CONST, 14u, (-1 << 16) - 1),
+      DEF_CONST(Instruction::CONST, 13u, shift_minus_1(16) + 1),
+      DEF_CONST(Instruction::CONST, 14u, shift_minus_1(16) - 1),
       // FP reg constants.
       DEF_CONST(Instruction::CONST_4, 15u, 0),
       DEF_CONST(Instruction::CONST_4, 16u, 1),
       DEF_CONST(Instruction::CONST_4, 17u, -1),
       DEF_CONST(Instruction::CONST_16, 18u, 1 << 4),
-      DEF_CONST(Instruction::CONST_16, 19u, -1 << 4),
+      DEF_CONST(Instruction::CONST_16, 19u, shift_minus_1(4)),
       DEF_CONST(Instruction::CONST_16, 20u, (1 << 4) + 1),
       DEF_CONST(Instruction::CONST_16, 21u, (1 << 4) - 1),
       DEF_CONST(Instruction::CONST_16, 22u, -(1 << 4) + 1),
@@ -893,8 +897,8 @@ TEST_F(LocalValueNumberingTest, Const) {
       DEF_CONST(Instruction::CONST_HIGH16, 25u, 0xffff),  // Effectively -1 << 16.
       DEF_CONST(Instruction::CONST, 26u, (1 << 16) + 1),
       DEF_CONST(Instruction::CONST, 27u, (1 << 16) - 1),
-      DEF_CONST(Instruction::CONST, 28u, (-1 << 16) + 1),
-      DEF_CONST(Instruction::CONST, 29u, (-1 << 16) - 1),
+      DEF_CONST(Instruction::CONST, 28u, shift_minus_1(16) + 1),
+      DEF_CONST(Instruction::CONST, 29u, shift_minus_1(16) - 1),
       // null reference constant.
       DEF_CONST(Instruction::CONST_4, 30u, 0),
   };

diff --git a/compiler/optimizing/constant_folding_test.cc b/compiler/optimizing/constant_folding_test.cc
index b2e222f..2feb75c 100644 (file)
--- a/compiler/optimizing/constant_folding_test.cc
+++ b/compiler/optimizing/constant_folding_test.cc
@@ -569,7 +569,7 @@ TEST(ConstantFolding, IntConstantFoldingAndJumps) {
     Instruction::ADD_INT_LIT16 | 1 << 8 | 0 << 12, 5,
     Instruction::GOTO | 4 << 8,
     Instruction::ADD_INT_LIT16 | 0 << 8 | 2 << 12, 4,
-    static_cast<uint16_t>(Instruction::GOTO | -5 << 8),
+    static_cast<uint16_t>(Instruction::GOTO | 0xFFFFFFFB << 8),
     Instruction::ADD_INT_LIT16 | 2 << 8 | 1 << 12, 8,
     Instruction::RETURN | 2 << 8);
 

diff --git a/compiler/optimizing/dead_code_elimination_test.cc b/compiler/optimizing/dead_code_elimination_test.cc
index cf0a4ac..2c6a1ef 100644 (file)
--- a/compiler/optimizing/dead_code_elimination_test.cc
+++ b/compiler/optimizing/dead_code_elimination_test.cc
@@ -140,7 +140,7 @@ TEST(DeadCodeElimination, AdditionsAndInconditionalJumps) {
     Instruction::ADD_INT_LIT16 | 1 << 8 | 0 << 12, 3,
     Instruction::GOTO | 4 << 8,
     Instruction::ADD_INT_LIT16 | 0 << 8 | 2 << 12, 2,
-    static_cast<uint16_t>(Instruction::GOTO | -5 << 8),
+    static_cast<uint16_t>(Instruction::GOTO | 0xFFFFFFFB << 8),
     Instruction::ADD_INT_LIT16 | 2 << 8 | 1 << 12, 4,
     Instruction::RETURN_VOID);
 

diff --git a/runtime/leb128_test.cc b/runtime/leb128_test.cc
index 09f7ecc..122f55e 100644 (file)
--- a/runtime/leb128_test.cc
+++ b/runtime/leb128_test.cc
@@ -88,7 +88,7 @@ static DecodeSignedLeb128TestCase sleb128_tests[] = {
     {-0x08000000, {0x80, 0x80, 0x80, 0x40, 0}},
     {-0x08000001, {0xFF, 0xFF, 0xFF, 0xBF, 0x7F}},
     {-0x20000000, {0x80, 0x80, 0x80, 0x80, 0x7E}},
-    {(-1) << 31, {0x80, 0x80, 0x80, 0x80, 0x78}},
+    {static_cast<int32_t>(0x80000000), {0x80, 0x80, 0x80, 0x80, 0x78}},
 };
 
 TEST(Leb128Test, UnsignedSinglesVector) {

diff --git a/runtime/reflection_test.cc b/runtime/reflection_test.cc
index bd89be5..c7c2709 100644 (file)
--- a/runtime/reflection_test.cc
+++ b/runtime/reflection_test.cc
@@ -157,7 +157,8 @@ class ReflectionTest : public CommonCompilerTest {
     result = InvokeWithJValues(soa, receiver_ref.get(), soa.EncodeMethod(method), args);
     EXPECT_EQ(SCHAR_MAX, result.GetB());
 
-    args[0].b = (SCHAR_MIN << 24) >> 24;
+    static_assert(SCHAR_MIN == -128, "SCHAR_MIN unexpected");
+    args[0].b = SCHAR_MIN;
     result = InvokeWithJValues(soa, receiver_ref.get(), soa.EncodeMethod(method), args);
     EXPECT_EQ(SCHAR_MIN, result.GetB());
   }