SpirvShader: Fix unused local warning in release builds.

Bug: b/123933266
Change-Id: I4585c881ea7328b03b7c98bd5b4c255a399a0a70
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/26532
Reviewed-by: Chris Forbes <chrisforbes@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Ben Clayton <bclayton@google.com>

src/Pipeline/SpirvShader.cpp

diff --git a/src/Pipeline/SpirvShader.cpp b/src/Pipeline/SpirvShader.cpp
index ad92a3e..87e071d8 100644
--- a/src/Pipeline/SpirvShader.cpp
+++ b/src/Pipeline/SpirvShader.cpp
@@ -1250,10 +1250,9 @@
 		TypeID typeId = insn.word(1);
 		ObjectID objectId = insn.word(2);
 		ObjectID baseId = insn.word(3);
-		auto &object = getObject(objectId);
 		auto &type = getType(typeId);
 		ASSERT(type.sizeInComponents == 1);
-		ASSERT(getObject(baseId).pointerBase == object.pointerBase);
+		ASSERT(getObject(baseId).pointerBase == getObject(objectId).pointerBase);
 
 		auto &dst = routine->createIntermediate(objectId, type.sizeInComponents);
 		dst.emplace(0, As<SIMD::Float>(WalkAccessChain(baseId, insn.wordCount() - 4, insn.wordPointer(4), routine)));