Mesa (master): intel/compiler: Cast to target type before shifting left

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Module: Mesa
Branch: master
Commit: 41623be20ee615fc5d2133c34b17b38e7d00146c
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=41623be20ee615fc5d2133c34b17b38e7d00146c

Author: Michel Dänzer <mdaenzer at redhat.com>
Date:   Wed Sep 25 11:31:23 2019 +0200

intel/compiler: Cast to target type before shifting left

Otherwise a smaller type may be promoted to int, which can hit undefined
behaviour:

../src/intel/compiler/brw_packed_float.c:66:17: runtime error: left shift of 128 by 24 places cannot be represented in type 'int'
    #0 0x5604a03969aa in brw_vf_to_float ../src/intel/compiler/brw_packed_float.c:66
    #1 0x5604a0391305 in vf_float_conversion_test_test_vf_to_float_Test::TestBody() ../src/intel/compiler/test_vf_float_conversions.cpp:70
    #2 0x5604a041a323 in void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) ../src/gtest/src/gtest.cc:2402
    #3 0x5604a0405c31 in void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) ../src/gtest/src/gtest.cc:2438
    #4 0x5604a03ab03b in testing::Test::Run() ../src/gtest/src/gtest.cc:2474
    #5 0x5604a03ad714 in testing::TestInfo::Run() ../src/gtest/src/gtest.cc:2656
    #6 0x5604a03afea2 in testing::TestCase::Run() ../src/gtest/src/gtest.cc:2774
    #7 0x5604a03cb87c in testing::internal::UnitTestImpl::RunAllTests() ../src/gtest/src/gtest.cc:4649
    #8 0x5604a041df3c in bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) ../src/gtest/src/gtest.cc:2402
    #9 0x5604a0409609 in bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) ../src/gtest/src/gtest.cc:2438
    #10 0x5604a03c2e9e in testing::UnitTest::Run() ../src/gtest/src/gtest.cc:4257
    #11 0x5604a0442d57 in RUN_ALL_TESTS() ../src/gtest/include/gtest/gtest.h:2233
    #12 0x5604a0442c17 in main ../src/gtest/src/gtest_main.cc:37
    #13 0x7f9a1983dbba in __libc_start_main ../csu/libc-start.c:308
    #14 0x5604a0390d89 in _start (/home/daenzer/src/mesa-git/mesa/build-amd64-sanitize/src/intel/compiler/vf_float_conversions+0x8dd89)

Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>
Reviewed-by: Adam Jackson <ajax at redhat.com>

---

 src/intel/compiler/brw_packed_float.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/intel/compiler/brw_packed_float.c b/src/intel/compiler/brw_packed_float.c
index 9b7687a756f..a97a176665b 100644
--- a/src/intel/compiler/brw_packed_float.c
+++ b/src/intel/compiler/brw_packed_float.c
@@ -63,7 +63,7 @@ brw_vf_to_float(unsigned char vf)
 
    /* ±0.0f is special cased. */
    if (vf == 0x00 || vf == 0x80) {
-      fu.u = vf << 24;
+      fu.u = (unsigned)vf << 24;
       return fu.f;
    }