commit 51d98676b0efc64398e026f4e0a3ab92a73f206f
author Nicolas Capens <capn@google.com> Tue Apr 02 12:05:40 2019 -0400
committer Nicolas Capens <nicolascapens@google.com> Tue Apr 02 18:05:15 2019 +0000
tree 19f412a1e054b8f86facf2edc3bdc42237e693fa
parent 3f20ba6b06fe1b979233e6f6f9c0bad11d569516

Fix materialization of function arguments

Subzero does not appear to preserve function arguments passed in as
registers onto the stack by itself. Any scratch registers can get reused
for local variable register allocation.

This workaround simply materializes each concrete Reactor variable
constructed from an argument on definition. It does not ensure that
arguments turned into variables at a later point are properly preserved.
Also this solution does not centralize the materialization, making it
bug prone when new concrete Reactor types are implemented.

Bug b/129757459

Change-Id: I1007ea0e7204d05e60203b2e896589a03fc515a9
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/28309
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>

src/Reactor/Reactor.cpp

diff --git a/src/Reactor/Reactor.cpp b/src/Reactor/Reactor.cpp
index b022533..80d12e0 100644
--- a/src/Reactor/Reactor.cpp
+++ b/src/Reactor/Reactor.cpp
@@ -89,6 +89,7 @@
 
 	Bool::Bool(Argument<Bool> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -164,6 +165,7 @@
 
 	Byte::Byte(Argument<Byte> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -421,6 +423,7 @@
 
 	SByte::SByte(Argument<SByte> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -666,6 +669,7 @@
 
 	Short::Short(Argument<Short> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -904,6 +908,7 @@
 
 	UShort::UShort(Argument<UShort> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -2119,6 +2124,7 @@
 
 	Int::Int(Argument<Int> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -2503,6 +2509,7 @@
 
 	UInt::UInt(Argument<UInt> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 
@@ -3662,6 +3669,7 @@
 
 	Float::Float(Argument<Float> argument)
 	{
+		materialize();  // FIXME(b/129757459)
 		storeValue(argument.value);
 	}
 

src/Reactor/Reactor.hpp

diff --git a/src/Reactor/Reactor.hpp b/src/Reactor/Reactor.hpp
index ee473a6..a0064b9 100644
--- a/src/Reactor/Reactor.hpp
+++ b/src/Reactor/Reactor.hpp
@@ -2626,6 +2626,7 @@
 	template<class T>
 	Pointer<T>::Pointer(Argument<Pointer<T>> argument) : alignment(1)
 	{
+		LValue<Pointer<T>>::materialize();  // FIXME(b/129757459)
 		LValue<Pointer<T>>::storeValue(argument.value);
 	}