[Beignet] [PATCH 1/4] rename endifOffset to needJump to make clear.

[xionghu.luo at intel.com]

From: Luo Xionghu <xionghu.luo at intel.com>

for conditional/unconditional backward jump, need insert JMPI instruction
in block header after LABEL instruction. same for unconditional forward
jump if the target is not the fallthrough block.

Signed-off-by: Luo Xionghu <xionghu.luo at intel.com>
---
 backend/src/backend/gen_insn_selection.cpp | 18 +++++++++---------
 backend/src/backend/gen_insn_selection.hpp |  3 ++-
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/backend/src/backend/gen_insn_selection.cpp b/backend/src/backend/gen_insn_selection.cpp
index dd21960..eb9e0ad 100644
--- a/backend/src/backend/gen_insn_selection.cpp
+++ b/backend/src/backend/gen_insn_selection.cpp
@@ -2496,7 +2496,7 @@ namespace gbe
     this->block->hasBranch = bb.getLastInstruction()->getOpcode() == OP_BRA ||
                              bb.getLastInstruction()->getOpcode() == OP_RET;
     if (!this->block->hasBranch)
-      this->block->endifOffset = -1;
+      this->block->needJump = -1;
 
     // Build the DAG on the fly
     uint32_t insnNum = 0;
@@ -6764,7 +6764,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
             // If jump to next label and the endif offset is -1, then
             // We don't need to add a jmpi here, as the following IF will do the same
             // thing if all channels are disabled.
-            (jip != nextLabel || sel.block->endifOffset != -1)) {
+            (jip != nextLabel || sel.block->needJump != -1)) {
           // If it is required, insert a JUMP to bypass the block
           sel.push();
             sel.curr.flag = 0;
@@ -7355,7 +7355,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
           sel.curr.predicate = GEN_PREDICATE_NONE;
           if (!sel.block->hasBarrier && !sel.block->removeSimpleIfEndif)
             sel.ENDIF(GenRegister::immd(0), nextLabel);
-          sel.block->endifOffset = -1;
+          sel.block->needJump = -1;
         sel.pop();
       } else {
         // Update the PcIPs
@@ -7371,7 +7371,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
           else if(insn.getParent()->needEndif)
             sel.ENDIF(GenRegister::immd(0), nextLabel);
         }
-        sel.block->endifOffset = -1;
+        sel.block->needJump = -1;
         if (nextLabel == jip) return;
         // Branch to the jump target
         sel.push();
@@ -7379,7 +7379,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
           sel.curr.noMask = 1;
           sel.curr.predicate = GEN_PREDICATE_NONE;
           // Actually, the origin of this JMPI should be the beginning of next BB.
-          sel.block->endifOffset -= sel.JMPI(GenRegister::immd(0), jip, ir::LabelIndex(curr->getLabelIndex().value() + 1));
+          sel.block->needJump -= sel.JMPI(GenRegister::immd(0), jip, ir::LabelIndex(curr->getLabelIndex().value() + 1));
         sel.pop();
       }
     }
@@ -7413,7 +7413,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
           sel.curr.flagIndex = pred.value();
           sel.curr.predicate = GEN_PREDICATE_NORMAL;
           sel.setBlockIP(ip, dst.value());
-          sel.block->endifOffset = -1;
+          sel.block->needJump = -1;
           sel.curr.predicate = GEN_PREDICATE_NONE;
           if (!sel.block->hasBarrier && !sel.block->removeSimpleIfEndif)
             sel.ENDIF(GenRegister::immd(0), next);
@@ -7423,7 +7423,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
           else
             sel.curr.predicate = GEN_PREDICATE_ALIGN1_ANY8H;
           sel.curr.noMask = 1;
-          sel.block->endifOffset -= sel.JMPI(GenRegister::immd(0), jip, label);
+          sel.block->needJump -= sel.JMPI(GenRegister::immd(0), jip, label);
         sel.pop();
       } else {
         const LabelIndex next = bb.getNextBlock()->getLabelIndex();
@@ -7432,7 +7432,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
         sel.curr.subFlag = 1;
         if(insn.getParent()->needEndif)
         sel.setBlockIP(ip, dst.value());
-        sel.block->endifOffset = -1;
+        sel.block->needJump = -1;
         if (!sel.block->hasBarrier && !sel.block->removeSimpleIfEndif) {
           if(insn.getParent()->needEndif && !insn.getParent()->needIf)
             sel.ENDIF(GenRegister::immd(0), insn.getParent()->endifLabel, insn.getParent()->endifLabel);
@@ -7444,7 +7444,7 @@ extern bool OCL_DEBUGINFO; // first defined by calling BVAR in program.cpp
           sel.curr.execWidth = 1;
           sel.curr.noMask = 1;
           sel.curr.predicate = GEN_PREDICATE_NONE;
-          sel.block->endifOffset -= sel.JMPI(GenRegister::immd(0), jip, label);
+          sel.block->needJump -= sel.JMPI(GenRegister::immd(0), jip, label);
         sel.pop();
       }
     }
diff --git a/backend/src/backend/gen_insn_selection.hpp b/backend/src/backend/gen_insn_selection.hpp
index 01999a2..61e2ee1 100644
--- a/backend/src/backend/gen_insn_selection.hpp
+++ b/backend/src/backend/gen_insn_selection.hpp
@@ -259,7 +259,8 @@ namespace gbe
     /*! Append a new selection instruction at the beginning of the block */
     void prepend(SelectionInstruction *insn);
     ir::LabelIndex endifLabel;
-    int endifOffset;
+    /*! need insert Jump instruction in block header after label instruction, -1 means not needed. */
+    int needJump;
     bool hasBarrier;
     bool hasBranch;
     bool removeSimpleIfEndif;
-- 
2.5.0