Relax the MemOperands on atomics a bit. Fixes -verify-machineinstrs failures for...

(The fix for the related failures on x86 is going to be nastier because we actually need Acquire memoperands attached to the atomic load instrs, etc.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139221 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h
index 2ecdc9a48c4ac1e4d6235a852b14d783f1035e00..6c7be69b4d2ff330134bb1a2f838841a5cfea49f 100644 (file)
--- a/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -998,8 +998,10 @@ class AtomicSDNode : public MemSDNode {
     assert(getOrdering() == Ordering && "Ordering encoding error!");
     assert(getSynchScope() == SynchScope && "Synch-scope encoding error!");
 
-    assert(readMem() && "Atomic MachineMemOperand is not a load!");
-    assert(writeMem() && "Atomic MachineMemOperand is not a store!");
+    assert((readMem() || getOrdering() <= Monotonic) &&
+           "Acquire/Release MachineMemOperand must be a load!");
+    assert((writeMem() || getOrdering() <= Monotonic) &&
+           "Acquire/Release MachineMemOperand must be a store!");
   }
 
 public:

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 5f5a880edfa7584d3c5ded4cb53f2f8f678815bf..19da986fe8e681dba9ea9fb9ea5589632064db6b 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3840,6 +3840,8 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT,
   unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore;
 
   // For now, atomics are considered to be volatile always.
+  // FIXME: Volatile isn't really correct; we should keep track of atomic
+  // orderings in the memoperand.
   Flags |= MachineMemOperand::MOVolatile;
 
   MachineMemOperand *MMO =
@@ -3889,9 +3891,16 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT,
     Alignment = getEVTAlignment(MemVT);
 
   MachineFunction &MF = getMachineFunction();
-  unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore;
+  // A monotonic store does not load; a release store "loads" in the sense
+  // that other stores cannot be sunk past it.
+  // (An atomicrmw obviously both loads and stores.)
+  unsigned Flags = MachineMemOperand::MOStore;
+  if (Opcode != ISD::ATOMIC_STORE || Ordering > Monotonic)
+    Flags |= MachineMemOperand::MOLoad;
 
   // For now, atomics are considered to be volatile always.
+  // FIXME: Volatile isn't really correct; we should keep track of atomic
+  // orderings in the memoperand.
   Flags |= MachineMemOperand::MOVolatile;
 
   MachineMemOperand *MMO =
@@ -3954,9 +3963,15 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT,
     Alignment = getEVTAlignment(MemVT);
 
   MachineFunction &MF = getMachineFunction();
-  unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore;
+  // A monotonic load does not store; an acquire load "stores" in the sense
+  // that other loads cannot be hoisted past it.
+  unsigned Flags = MachineMemOperand::MOLoad;
+  if (Ordering > Monotonic)
+    Flags |= MachineMemOperand::MOStore;
 
   // For now, atomics are considered to be volatile always.
+  // FIXME: Volatile isn't really correct; we should keep track of atomic
+  // orderings in the memoperand.
   Flags |= MachineMemOperand::MOVolatile;
 
   MachineMemOperand *MMO =

diff --git a/test/CodeGen/ARM/atomic-load-store.ll b/test/CodeGen/ARM/atomic-load-store.ll
index 81c828485e611a4e1adc49de0b0687d5b01d24c4..4d6b403ce94adb87740d18bae6725c62e10ddbf2 100644 (file)
--- a/test/CodeGen/ARM/atomic-load-store.ll
+++ b/test/CodeGen/ARM/atomic-load-store.ll
@@ -1,4 +1,4 @@
-; RUN: llc < %s -mtriple=armv7-apple-ios | FileCheck %s -check-prefix=ARM
+; RUN: llc < %s -mtriple=armv7-apple-ios -verify-machineinstrs | FileCheck %s -check-prefix=ARM
 ; RUN: llc < %s -mtriple=armv7-apple-ios -O0 | FileCheck %s -check-prefix=ARM
 ; RUN: llc < %s -mtriple=thumbv7-apple-ios | FileCheck %s -check-prefix=THUMBTWO
 ; RUN: llc < %s -mtriple=thumbv6-apple-ios | FileCheck %s -check-prefix=THUMBONE