From 04a573a41f037eae148f70bf2038602f7e32dd71 Mon Sep 17 00:00:00 2001
From: Robert Lytton <robert@xmos.com>
Date: Tue, 11 Feb 2014 10:36:18 +0000
Subject:  XCore target: Lower ATOMIC_LOAD & ATOMIC_STORE

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201143 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/XCore/XCoreISelLowering.cpp | 68 ++++++++++++++++++++++++++++++++++
 lib/Target/XCore/XCoreISelLowering.h   |  2 +
 2 files changed, 70 insertions(+)

(limited to 'lib')

diff --git a/lib/Target/XCore/XCoreISelLowering.cpp b/lib/Target/XCore/XCoreISelLowering.cpp
index dd268c4cdd..82ad0d069a 100644
--- a/lib/Target/XCore/XCoreISelLowering.cpp
+++ b/lib/Target/XCore/XCoreISelLowering.cpp
@@ -159,7 +159,12 @@ XCoreTargetLowering::XCoreTargetLowering(XCoreTargetMachine &XTM)
   setOperationAction(ISD::FRAME_TO_ARGS_OFFSET, MVT::i32, Custom);
 
   // Atomic operations
+  // We request a fence for ATOMIC_* instructions, to reduce them to Monotonic.
+  // As we are always Sequential Consistent, an ATOMIC_FENCE becomes a no OP.
+  setInsertFencesForAtomic(true);
   setOperationAction(ISD::ATOMIC_FENCE, MVT::Other, Custom);
+  setOperationAction(ISD::ATOMIC_LOAD, MVT::i32, Custom);
+  setOperationAction(ISD::ATOMIC_STORE, MVT::i32, Custom);
 
   // TRAMPOLINE is custom lowered.
   setOperationAction(ISD::INIT_TRAMPOLINE, MVT::Other, Custom);
@@ -223,6 +228,8 @@ LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   case ISD::ADJUST_TRAMPOLINE:  return LowerADJUST_TRAMPOLINE(Op, DAG);
   case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
   case ISD::ATOMIC_FENCE:       return LowerATOMIC_FENCE(Op, DAG);
+  case ISD::ATOMIC_LOAD:        return LowerATOMIC_LOAD(Op, DAG);
+  case ISD::ATOMIC_STORE:       return LowerATOMIC_STORE(Op, DAG);
   default:
     llvm_unreachable("unimplemented operand");
   }
@@ -964,6 +971,67 @@ LowerATOMIC_FENCE(SDValue Op, SelectionDAG &DAG) const {
   return DAG.getNode(XCoreISD::MEMBARRIER, DL, MVT::Other, Op.getOperand(0));
 }
 
+SDValue XCoreTargetLowering::
+LowerATOMIC_LOAD(SDValue Op, SelectionDAG &DAG) const {
+  AtomicSDNode *N = cast<AtomicSDNode>(Op);
+  assert(N->getOpcode() == ISD::ATOMIC_LOAD && "Bad Atomic OP");
+  assert(N->getOrdering() <= Monotonic &&
+         "setInsertFencesForAtomic(true) and yet greater than Monotonic");
+  if (N->getMemoryVT() == MVT::i32) {
+    if (N->getAlignment() < 4)
+      report_fatal_error("atomic load must be aligned");
+    return DAG.getLoad(getPointerTy(), SDLoc(Op), N->getChain(),
+                       N->getBasePtr(), N->getPointerInfo(),
+                       N->isVolatile(), N->isNonTemporal(),
+                       N->isInvariant(), N->getAlignment(),
+                       N->getTBAAInfo(), N->getRanges());
+  }
+  if (N->getMemoryVT() == MVT::i16) {
+    if (N->getAlignment() < 2)
+      report_fatal_error("atomic load must be aligned");
+    return DAG.getExtLoad(ISD::EXTLOAD, SDLoc(Op), MVT::i32, N->getChain(),
+                          N->getBasePtr(), N->getPointerInfo(), MVT::i16,
+                          N->isVolatile(), N->isNonTemporal(),
+                          N->getAlignment(), N->getTBAAInfo());
+  }
+  if (N->getMemoryVT() == MVT::i8)
+    return DAG.getExtLoad(ISD::EXTLOAD, SDLoc(Op), MVT::i32, N->getChain(),
+                          N->getBasePtr(), N->getPointerInfo(), MVT::i8,
+                          N->isVolatile(), N->isNonTemporal(),
+                          N->getAlignment(), N->getTBAAInfo());
+  return SDValue();
+}
+
+SDValue XCoreTargetLowering::
+LowerATOMIC_STORE(SDValue Op, SelectionDAG &DAG) const {
+  AtomicSDNode *N = cast<AtomicSDNode>(Op);
+  assert(N->getOpcode() == ISD::ATOMIC_STORE && "Bad Atomic OP");
+  assert(N->getOrdering() <= Monotonic &&
+         "setInsertFencesForAtomic(true) and yet greater than Monotonic");
+  if (N->getMemoryVT() == MVT::i32) {
+    if (N->getAlignment() < 4)
+      report_fatal_error("atomic store must be aligned");
+    return DAG.getStore(N->getChain(), SDLoc(Op), N->getVal(),
+                        N->getBasePtr(), N->getPointerInfo(),
+                        N->isVolatile(), N->isNonTemporal(),
+                        N->getAlignment(), N->getTBAAInfo());
+  }
+  if (N->getMemoryVT() == MVT::i16) {
+    if (N->getAlignment() < 2)
+      report_fatal_error("atomic store must be aligned");
+    return DAG.getTruncStore(N->getChain(), SDLoc(Op), N->getVal(),
+                             N->getBasePtr(), N->getPointerInfo(), MVT::i16,
+                             N->isVolatile(), N->isNonTemporal(),
+                             N->getAlignment(), N->getTBAAInfo());
+  }
+  if (N->getMemoryVT() == MVT::i8)
+    return DAG.getTruncStore(N->getChain(), SDLoc(Op), N->getVal(),
+                             N->getBasePtr(), N->getPointerInfo(), MVT::i8,
+                             N->isVolatile(), N->isNonTemporal(),
+                             N->getAlignment(), N->getTBAAInfo());
+  return SDValue();
+}
+
 //===----------------------------------------------------------------------===//
 //                      Calling Convention Implementation
 //===----------------------------------------------------------------------===//
diff --git a/lib/Target/XCore/XCoreISelLowering.h b/lib/Target/XCore/XCoreISelLowering.h
index 05e2a86a9b..e05068f773 100644
--- a/lib/Target/XCore/XCoreISelLowering.h
+++ b/lib/Target/XCore/XCoreISelLowering.h
@@ -172,6 +172,8 @@ namespace llvm {
     SDValue LowerADJUST_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const;
     SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const;
     SDValue LowerATOMIC_FENCE(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerATOMIC_LOAD(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerATOMIC_STORE(SDValue Op, SelectionDAG &DAG) const;
 
     // Inline asm support
     std::pair<unsigned, const TargetRegisterClass*>
-- 
cgit v1.2.3