From 69420c28bdc8b7100252bf167475ab2ff29f7693 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Michel=20D=C3=A4nzer?= Date: Wed, 25 Sep 2019 11:44:24 +0200 Subject: [PATCH] util: Use uint64_t for shifting left in sign_extend and strunc Shifting int64_t values left into the sign bit has undefined behaviour: ../src/util/fast_idiv_by_const.c:175:14: runtime error: left shift of 131 by 56 places cannot be represented in type 'long int' #0 0x561337ed10c1 in sign_extend ../src/util/fast_idiv_by_const.c:175 #1 0x561337ed1335 in util_compute_fast_sdiv_info ../src/util/fast_idiv_by_const.c:239 #2 0x561337e17519 in fast_idiv_by_const_int8_Test::TestBody() ../src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp:357 #3 0x561337ea815d in void testing::internal::HandleSehExceptionsInMethodIfSupported(testing::Test*, void (testing::Test::*)(), char const*) ../src/gtest/src/gtest.cc:2402 #4 0x561337e93a6b in void testing::internal::HandleExceptionsInMethodIfSupported(testing::Test*, void (testing::Test::*)(), char const*) ../src/gtest/src/gtest.cc:2438 #5 0x561337e38e75 in testing::Test::Run() ../src/gtest/src/gtest.cc:2474 #6 0x561337e3b54e in testing::TestInfo::Run() ../src/gtest/src/gtest.cc:2656 #7 0x561337e3dcdc in testing::TestCase::Run() ../src/gtest/src/gtest.cc:2774 #8 0x561337e596b6 in testing::internal::UnitTestImpl::RunAllTests() ../src/gtest/src/gtest.cc:4649 #9 0x561337eabd76 in bool testing::internal::HandleSehExceptionsInMethodIfSupported(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) ../src/gtest/src/gtest.cc:2402 #10 0x561337e97443 in bool testing::internal::HandleExceptionsInMethodIfSupported(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) ../src/gtest/src/gtest.cc:2438 #11 0x561337e50cd8 in testing::UnitTest::Run() ../src/gtest/src/gtest.cc:4257 #12 0x561337ed0b91 in RUN_ALL_TESTS() ../src/gtest/include/gtest/gtest.h:2233 #13 0x561337ed0a51 in main ../src/gtest/src/gtest_main.cc:37 #14 0x7f85ba483bba in __libc_start_main ../csu/libc-start.c:308 #15 0x561337e14dc9 in _start (/home/daenzer/src/mesa-git/mesa/build-amd64-sanitize/src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test+0x96dc9) ../src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp:51:14: runtime error: left shift of negative value -63 #0 0x55fc3c0e67cc in strunc ../src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp:51 #1 0x55fc3c0e6d93 in smul_high ../src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp:140 #2 0x55fc3c0e7067 in fast_sdiv ../src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp:181 #3 0x55fc3c0e858b in fast_idiv_by_const_int8_Test::TestBody() ../src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp:358 #4 0x55fc3c17915d in void testing::internal::HandleSehExceptionsInMethodIfSupported(testing::Test*, void (testing::Test::*)(), char const*) ../src/gtest/src/gtest.cc:2402 #5 0x55fc3c164a6b in void testing::internal::HandleExceptionsInMethodIfSupported(testing::Test*, void (testing::Test::*)(), char const*) ../src/gtest/src/gtest.cc:2438 #6 0x55fc3c109e75 in testing::Test::Run() ../src/gtest/src/gtest.cc:2474 #7 0x55fc3c10c54e in testing::TestInfo::Run() ../src/gtest/src/gtest.cc:2656 #8 0x55fc3c10ecdc in testing::TestCase::Run() ../src/gtest/src/gtest.cc:2774 #9 0x55fc3c12a6b6 in testing::internal::UnitTestImpl::RunAllTests() ../src/gtest/src/gtest.cc:4649 #10 0x55fc3c17cd76 in bool testing::internal::HandleSehExceptionsInMethodIfSupported(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) ../src/gtest/src/gtest.cc:2402 #11 0x55fc3c168443 in bool testing::internal::HandleExceptionsInMethodIfSupported(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) ../src/gtest/src/gtest.cc:2438 #12 0x55fc3c121cd8 in testing::UnitTest::Run() ../src/gtest/src/gtest.cc:4257 #13 0x55fc3c1a1b91 in RUN_ALL_TESTS() ../src/gtest/include/gtest/gtest.h:2233 #14 0x55fc3c1a1a51 in main ../src/gtest/src/gtest_main.cc:37 #15 0x7fd224759bba in __libc_start_main ../csu/libc-start.c:308 #16 0x55fc3c0e5dc9 in _start (/home/daenzer/src/mesa-git/mesa/build-amd64-sanitize/src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test+0x96dc9) v2: * Use two casts instead of changing the argument type (Jason Ekstrand) Reviewed-by: Jason Ekstrand Reviewed-by: Adam Jackson --- src/util/fast_idiv_by_const.c | 2 +- src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/src/util/fast_idiv_by_const.c b/src/util/fast_idiv_by_const.c index 7b93316268c..4f0f6b769b8 100644 --- a/src/util/fast_idiv_by_const.c +++ b/src/util/fast_idiv_by_const.c @@ -172,7 +172,7 @@ util_compute_fast_udiv_info(uint64_t D, unsigned num_bits, unsigned UINT_BITS) static inline int64_t sign_extend(int64_t x, unsigned SINT_BITS) { - return (x << (64 - SINT_BITS)) >> (64 - SINT_BITS); + return (int64_t)((uint64_t)x << (64 - SINT_BITS)) >> (64 - SINT_BITS); } struct util_fast_sdiv_info diff --git a/src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp b/src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp index b0b3669e73b..222346230e4 100644 --- a/src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp +++ b/src/util/tests/fast_idiv_by_const/fast_idiv_by_const_test.cpp @@ -48,7 +48,7 @@ strunc(int64_t x, unsigned num_bits) if (num_bits == 64) return x; - return (x << (64 - num_bits)) >> (64 - num_bits); + return (int64_t)((uint64_t)x << (64 - num_bits)) >> (64 - num_bits); } static inline bool -- 2.30.2