From d5cb4a90e56af1eb1cd41a33b1c1c421bd88dbca Mon Sep 17 00:00:00 2001
From: Krzysztof Parzyszek <kparzysz@codeaurora.org>
Date: Wed, 18 Mar 2015 15:56:43 +0000
Subject: [PATCH] [Hexagon] Handle ENDLOOP0 in InsertBranch and RemoveBranch

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232643 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/Hexagon/HexagonInstrInfo.cpp | 47 ++++++++++++++++++++-------------
 test/CodeGen/Hexagon/hwloop-cleanup.ll  |  3 ++-
 2 files changed, 30 insertions(+), 20 deletions(-)

diff --git a/lib/Target/Hexagon/HexagonInstrInfo.cpp b/lib/Target/Hexagon/HexagonInstrInfo.cpp
index 5556ae9b3c5..92ed96877a0 100644
--- a/lib/Target/Hexagon/HexagonInstrInfo.cpp
+++ b/lib/Target/Hexagon/HexagonInstrInfo.cpp
@@ -157,15 +157,19 @@ HexagonInstrInfo::InsertBranch(MachineBasicBlock &MBB,MachineBasicBlock *TBB,
         }
         BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB);
       } else {
-        BuildMI(&MBB, DL,
-                get(BccOpc)).addReg(Cond[regPos].getReg()).addMBB(TBB);
+        // If Cond[0] is a basic block, insert ENDLOOP0.
+        if (Cond[0].isMBB())
+          BuildMI(&MBB, DL, get(Hexagon::ENDLOOP0)).addMBB(Cond[0].getMBB());
+        else
+          BuildMI(&MBB, DL,
+                  get(BccOpc)).addReg(Cond[regPos].getReg()).addMBB(TBB);
       }
       return 1;
     }
 
+    // We don't handle ENDLOOP0 with a conditional branch in AnalyzeBranch.
     BuildMI(&MBB, DL, get(BccOpc)).addReg(Cond[regPos].getReg()).addMBB(TBB);
     BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB);
-
     return 2;
 }
 
@@ -314,30 +318,35 @@ bool HexagonInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
 
 
 unsigned HexagonInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
-  int BOpc   = Hexagon::J2_jump;
-  int BccOpc = Hexagon::J2_jumpt;
-  int BccOpcNot = Hexagon::J2_jumpf;
-
   MachineBasicBlock::iterator I = MBB.end();
   if (I == MBB.begin()) return 0;
   --I;
-  if (I->getOpcode() != BOpc && I->getOpcode() != BccOpc &&
-      I->getOpcode() != BccOpcNot)
-    return 0;
-
-  // Remove the branch.
-  I->eraseFromParent();
+  unsigned Opc1 = I->getOpcode();
+  switch (Opc1) {
+    case Hexagon::J2_jump:
+    case Hexagon::J2_jumpt:
+    case Hexagon::J2_jumpf:
+    case Hexagon::ENDLOOP0:
+      I->eraseFromParent();
+      break;
+    default:
+      return 0;
+  }
 
   I = MBB.end();
 
   if (I == MBB.begin()) return 1;
   --I;
-  if (I->getOpcode() != BccOpc && I->getOpcode() != BccOpcNot)
-    return 1;
-
-  // Remove the branch.
-  I->eraseFromParent();
-  return 2;
+  unsigned Opc2 = I->getOpcode();
+  switch (Opc2) {
+    case Hexagon::J2_jumpt:
+    case Hexagon::J2_jumpf:
+    case Hexagon::ENDLOOP0:
+      I->eraseFromParent();
+      return 2;
+    default:
+      return 1;
+  }
 }
 
 
diff --git a/test/CodeGen/Hexagon/hwloop-cleanup.ll b/test/CodeGen/Hexagon/hwloop-cleanup.ll
index 643fe11f2cb..c04966a5a4b 100644
--- a/test/CodeGen/Hexagon/hwloop-cleanup.ll
+++ b/test/CodeGen/Hexagon/hwloop-cleanup.ll
@@ -1,4 +1,5 @@
-; RUN: llc -march=hexagon -mcpu=hexagonv4 < %s | FileCheck %s
+; RUN: llc -march=hexagon -mcpu=hexagonv4 -no-phi-elim-live-out-early-exit \
+; RUN:    < %s | FileCheck %s
 ; Check that we remove the compare and induction variable instructions
 ; after generating hardware loops.
 ; Bug 6685.
-- 
2.11.0