[Beignet] [PATCH 17/18] GBE: avoid use a temporay register at the CMP instruction.

[Zhigang Gong]

Use one SEL instruction, we can easily transfer a flag
to a normal bool vector register with correct mask.

Signed-off-by: Zhigang Gong <zhigang.gong at intel.com>
---
 backend/src/backend/gen_context.cpp        |  9 ---------
 backend/src/backend/gen_insn_selection.cpp | 32 ++++++++++++++++++++----------
 2 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/backend/src/backend/gen_context.cpp b/backend/src/backend/gen_context.cpp
index ec778d2..518da99 100644
--- a/backend/src/backend/gen_context.cpp
+++ b/backend/src/backend/gen_context.cpp
@@ -1077,7 +1077,6 @@ namespace gbe
     GenRegister tmp0 = ra->genReg(insn.dst(0));
     GenRegister tmp1 = ra->genReg(insn.dst(1));
     GenRegister tmp2 = ra->genReg(insn.dst(2));
-    GenRegister dst = ra->genReg(insn.dst(3));
     tmp0.type = (src0.type == GEN_TYPE_L) ? GEN_TYPE_D : GEN_TYPE_UD;
     tmp1.type = (src1.type == GEN_TYPE_L) ? GEN_TYPE_D : GEN_TYPE_UD;
     int flag = p->curr.flag, subFlag = p->curr.subFlag;
@@ -1150,14 +1149,6 @@ namespace gbe
     p->curr.execWidth = 1;
     p->MOV(GenRegister::flag(flag, subFlag), f1);
     p->pop();
-    p->push();
-    p->curr.predicate = GEN_PREDICATE_NONE;
-    p->curr.noMask = 1;
-    p->MOV(dst, GenRegister::immd(0));
-    p->curr.noMask = 0;
-    p->curr.predicate = GEN_PREDICATE_NORMAL;
-    p->MOV(dst, GenRegister::immd(-1));
-    p->pop();
   }
 
   void GenContext::emitI64SATADDInstruction(const SelectionInstruction &insn) {
diff --git a/backend/src/backend/gen_insn_selection.cpp b/backend/src/backend/gen_insn_selection.cpp
index a7baf72..a26aed7 100644
--- a/backend/src/backend/gen_insn_selection.cpp
+++ b/backend/src/backend/gen_insn_selection.cpp
@@ -486,7 +486,7 @@ namespace gbe
     /*! Shift a 64-bit integer */
     void I64Shift(SelectionOpcode opcode, Reg dst, Reg src0, Reg src1, GenRegister tmp[7]);
     /*! Compare 64-bit integer */
-    void I64CMP(uint32_t conditional, Reg src0, Reg src1, GenRegister tmp[3], Reg dst = GenRegister::null());
+    void I64CMP(uint32_t conditional, Reg src0, Reg src1, GenRegister tmp[3]);
     /*! Saturated addition of 64-bit integer */
     void I64SATADD(Reg dst, Reg src0, Reg src1, GenRegister tmp[6]);
     /*! Saturated subtraction of 64-bit integer */
@@ -1244,13 +1244,12 @@ namespace gbe
     insn->src(2) = src2;
   }
 
-  void Selection::Opaque::I64CMP(uint32_t conditional, Reg src0, Reg src1, GenRegister tmp[3], Reg dst) {
-    SelectionInstruction *insn = this->appendInsn(SEL_OP_I64CMP, 4, 2);
+  void Selection::Opaque::I64CMP(uint32_t conditional, Reg src0, Reg src1, GenRegister tmp[3]) {
+    SelectionInstruction *insn = this->appendInsn(SEL_OP_I64CMP, 3, 2);
     insn->src(0) = src0;
     insn->src(1) = src1;
     for(int i=0; i<3; i++)
       insn->dst(i) = tmp[i];
-    insn->dst(3) = dst;
     insn->extra.function = conditional;
   }
 
@@ -2657,11 +2656,12 @@ namespace gbe
       const Type type = insn.getType();
       const Register dst = insn.getDst(0);
       GenRegister tmpDst;
-
-      if (type == TYPE_BOOL || type == TYPE_U16 || type == TYPE_S16)
-        tmpDst = sel.selReg(dst, TYPE_BOOL);
+      if(type == TYPE_S64 || type == TYPE_U64 ||
+         type == TYPE_DOUBLE || type == TYPE_FLOAT ||
+         type == TYPE_U32 ||  type == TYPE_S32 )
+        tmpDst = GenRegister::nullud();
       else
-        tmpDst = sel.selReg(sel.reg(FAMILY_DWORD), TYPE_S32);
+        tmpDst = sel.selReg(dst, TYPE_BOOL);
 
       // Look for immediate values for the right source
       GenRegister src0, src1;
@@ -2691,7 +2691,7 @@ namespace gbe
           GenRegister tmp[3];
           for(int i=0; i<3; i++)
             tmp[i] = sel.selReg(sel.reg(FAMILY_DWORD));
-          sel.I64CMP(getGenCompare(opcode), src0, src1, tmp, tmpDst);
+          sel.I64CMP(getGenCompare(opcode), src0, src1, tmp);
         } else if(opcode == OP_ORD) {
           sel.push();
             sel.CMP(GEN_CONDITIONAL_EQ, src0, src0, tmpDst);
@@ -2702,8 +2702,18 @@ namespace gbe
           sel.CMP(getGenCompare(opcode), src0, src1, tmpDst);
       sel.pop();
 
-      if (!(type == TYPE_BOOL || type == TYPE_U16 || type == TYPE_S16))
-        sel.MOV(sel.selReg(dst, TYPE_U16), GenRegister::unpacked_uw((ir::Register)tmpDst.value.reg));
+      if(type == TYPE_S64 || type == TYPE_U64 ||
+         type == TYPE_DOUBLE || type == TYPE_FLOAT ||
+         type == TYPE_U32 ||  type == TYPE_S32 ) {
+        sel.push();
+          sel.curr.flag = 1;
+          sel.curr.subFlag = 1;
+          sel.curr.predicate = GEN_PREDICATE_NORMAL;
+          sel.SEL(sel.selReg(dst, TYPE_U16),
+                  sel.selReg(ir::ocl::one, TYPE_U16),
+                  sel.selReg(ir::ocl::zero, TYPE_U16));
+        sel.pop();
+      }
       return true;
     }
   };
-- 
1.8.3.2