Fix initializing bits after bitfields
SpirvShader::InterfaceComponent is used as part of the state that
comprises the lookup key for cached Reactor routines. It uses 1-bit
bitfields for Boolean values, and the bits following it for padding may
be left uninitialized by the compiler. Computing the hash of all the
state is done by XORing together the memory, so it shouldn't have any-
thing uninitialized. While we memset all of SetupProcessor::State to 0,
the InterfaceComponent state copied in still contained the uninitialized
bits. Computing a hash from it was detected by MemorySanitizer.
Bug chromium:967824
Change-Id: If1676831fc838bf2a6ca869d13e6f6d2052fa6d8
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/32128
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Sean Risser <srisser@google.com>
diff --git a/src/Pipeline/SpirvShader.hpp b/src/Pipeline/SpirvShader.hpp
index 09cf15b..c6fd58f 100644
--- a/src/Pipeline/SpirvShader.hpp
+++ b/src/Pipeline/SpirvShader.hpp
@@ -656,12 +656,21 @@
struct InterfaceComponent
{
AttribType Type;
- bool Flat : 1;
- bool Centroid : 1;
- bool NoPerspective : 1;
+
+ union
+ {
+ struct
+ {
+ bool Flat : 1;
+ bool Centroid : 1;
+ bool NoPerspective : 1;
+ };
+
+ uint8_t DecorationBits;
+ };
InterfaceComponent()
- : Type{ATTRIBTYPE_UNUSED}, Flat{false}, Centroid{false}, NoPerspective{false}
+ : Type{ATTRIBTYPE_UNUSED}, DecorationBits{0}
{
}
};
