[Beignet] [PATCH 2/2] GBE: fix the constant data allocation.

[Zhigang Gong]

From: Zhigang Gong <zhigang.gong at linux.intel.com>

Need to keep consistency between the constant data
allocation and the constant register allocation.
So we need to skip the unused constant data at the
constant data allocation stage.

To avoid possible mismatching, add a new assert in
the constant register(address) allocation stage to
make sure the address register match the eaxct constant
data.

Also modify the constant utest slightly to hit this
code path.

Signed-off-by: Zhigang Gong <zhigang.gong at linux.intel.com>
---
 backend/src/llvm/llvm_gen_backend.cpp |    2 ++
 kernels/compiler_global_constant.cl   |    2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/backend/src/llvm/llvm_gen_backend.cpp b/backend/src/llvm/llvm_gen_backend.cpp
index a104df4..5421fdc 100644
--- a/backend/src/llvm/llvm_gen_backend.cpp
+++ b/backend/src/llvm/llvm_gen_backend.cpp
@@ -681,6 +681,7 @@ namespace gbe
     const Module::GlobalListType &globalList = TheModule->getGlobalList();
     for(auto i = globalList.begin(); i != globalList.end(); i ++) {
       const GlobalVariable &v = *i;
+      if(!v.isConstantUsed()) continue;
       const char *name = v.getName().data();
       unsigned addrSpace = v.getType()->getAddressSpace();
       if(addrSpace == ir::AddressSpace::MEM_CONSTANT) {
@@ -1380,6 +1381,7 @@ namespace gbe
         this->newRegister(const_cast<GlobalVariable*>(&v));
         ir::Register reg = regTranslator.getScalar(const_cast<GlobalVariable*>(&v), 0);
         ir::Constant &con = unit.getConstantSet().getConstant(j ++);
+        GBE_ASSERT(con.getName() == v.getName());
         ctx.LOADI(ir::TYPE_S32, reg, ctx.newIntegerImmediate(con.getOffset(), ir::TYPE_S32));
       } else {
         GBE_ASSERT(0);
diff --git a/kernels/compiler_global_constant.cl b/kernels/compiler_global_constant.cl
index 53e24b3..c0e23d1 100644
--- a/kernels/compiler_global_constant.cl
+++ b/kernels/compiler_global_constant.cl
@@ -1,5 +1,5 @@
 constant int m[3] = {71,72,73};
-constant int n = 1;
+const constant int n = 1;
 constant int o[3] = {3, 2, 1};
 
 constant int4 a= {1, 2, 3, 4};
-- 
1.7.9.5