[Beignet] [PATCH 16/18] GBE: Add two helper scalar registers to hold 0 and all 1s.

[Zhigang Gong]

Signed-off-by: Zhigang Gong <zhigang.gong at intel.com>
---
 backend/src/backend/gen_context.cpp | 9 +++++++++
 backend/src/backend/program.h       | 2 ++
 backend/src/ir/profile.cpp          | 6 ++++--
 backend/src/ir/profile.hpp          | 6 ++++--
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/backend/src/backend/gen_context.cpp b/backend/src/backend/gen_context.cpp
index 6cfeca4..ec778d2 100644
--- a/backend/src/backend/gen_context.cpp
+++ b/backend/src/backend/gen_context.cpp
@@ -105,12 +105,19 @@ namespace gbe
     // when group size not aligned to simdWidth, flag register need clear to
     // make prediction(any8/16h) work correctly
     const GenRegister blockip = ra->genReg(GenRegister::uw8grf(ir::ocl::blockip));
+    const GenRegister zero = ra->genReg(GenRegister::uw1grf(ir::ocl::zero));
+    const GenRegister one = ra->genReg(GenRegister::uw1grf(ir::ocl::one));
     p->push();
       p->curr.noMask = 1;
       p->curr.predicate = GEN_PREDICATE_NONE;
       p->MOV(blockip, GenRegister::immuw(GEN_MAX_LABEL));
       p->curr.noMask = 0;
       p->MOV(blockip, GenRegister::immuw(0));
+      p->curr.execWidth = 1;
+      // FIXME, need to get the final use set of zero/one, if there is no user,
+      // no need to generate the following two instructions.
+      p->MOV(zero, GenRegister::immuw(0));
+      p->MOV(one, GenRegister::immw(-1));
     p->pop();
   }
 
@@ -1902,6 +1909,8 @@ namespace gbe
     allocCurbeReg(lid0, GBE_CURBE_LOCAL_ID_X);
     allocCurbeReg(lid1, GBE_CURBE_LOCAL_ID_Y);
     allocCurbeReg(lid2, GBE_CURBE_LOCAL_ID_Z);
+    allocCurbeReg(zero, GBE_CURBE_ZERO);
+    allocCurbeReg(one, GBE_CURBE_ONE);
     if (stackUse.size() != 0)
       allocCurbeReg(stackbuffer, GBE_CURBE_EXTRA_ARGUMENT, GBE_STACK_BUFFER);
     // Go over the arguments and find the related patch locations
diff --git a/backend/src/backend/program.h b/backend/src/backend/program.h
index 4ca7277..c22793e 100644
--- a/backend/src/backend/program.h
+++ b/backend/src/backend/program.h
@@ -76,6 +76,8 @@ enum gbe_curbe_type {
   GBE_CURBE_EXTRA_ARGUMENT,
   GBE_CURBE_BLOCK_IP,
   GBE_CURBE_THREAD_NUM,
+  GBE_CURBE_ZERO,
+  GBE_CURBE_ONE,
 };
 
 /*! Extra arguments use the negative range of sub-values */
diff --git a/backend/src/ir/profile.cpp b/backend/src/ir/profile.cpp
index 2a1bb41..ddf53d1 100644
--- a/backend/src/ir/profile.cpp
+++ b/backend/src/ir/profile.cpp
@@ -39,8 +39,8 @@ namespace ir {
         "global_offset_0", "global_offset_1", "global_offset_2",
         "stack_pointer", "stack_buffer",
         "block_ip",
-        "barrier_id", "thread_number",
-        "work_dimension",
+        "barrier_id", "thread_number", "work_dimension",
+        "zero", "one",
         "retVal"
     };
 
@@ -78,6 +78,8 @@ namespace ir {
       DECL_NEW_REG(FAMILY_DWORD, barrierid, 1);
       DECL_NEW_REG(FAMILY_DWORD, threadn, 1);
       DECL_NEW_REG(FAMILY_DWORD, workdim, 1);
+      DECL_NEW_REG(FAMILY_DWORD, zero, 1);
+      DECL_NEW_REG(FAMILY_DWORD, one, 1);
       DECL_NEW_REG(FAMILY_WORD, retVal, 1);
     }
 #undef DECL_NEW_REG
diff --git a/backend/src/ir/profile.hpp b/backend/src/ir/profile.hpp
index c4763c8..0652a25 100644
--- a/backend/src/ir/profile.hpp
+++ b/backend/src/ir/profile.hpp
@@ -65,8 +65,10 @@ namespace ir {
     static const Register barrierid = Register(21);// barrierid
     static const Register threadn = Register(22);  // number of threads
     static const Register workdim = Register(23);  // work dimention.
-    static const Register retVal = Register(24);   // helper register to do data flow analysis.
-    static const uint32_t regNum = 25;             // number of special registers
+    static const Register zero = Register(24);     //  scalar register holds zero.
+    static const Register one = Register(25);     //  scalar register holds one. 
+    static const Register retVal = Register(26);   // helper register to do data flow analysis.
+    static const uint32_t regNum = 27;             // number of special registers
     extern const char *specialRegMean[];           // special register name.
   } /* namespace ocl */
 
-- 
1.8.3.2