[llvm-commits] [llvm] r139221 - in /llvm/trunk: include/llvm/CodeGen/SelectionDAGNodes.h lib/CodeGen/SelectionDAG/SelectionDAG.cpp test/CodeGen/ARM/atomic-load-store.ll

[Eli Friedman]

Author: efriedma
Date: Tue Sep  6 21:23:42 2011
New Revision: 139221

URL: http://llvm.org/viewvc/llvm-project?rev=139221&view=rev
Log:
Relax the MemOperands on atomics a bit.  Fixes -verify-machineinstrs failures for atomic laod/store on ARM.

(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.)


Modified:
    llvm/trunk/include/llvm/CodeGen/SelectionDAGNodes.h
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    llvm/trunk/test/CodeGen/ARM/atomic-load-store.ll

Modified: llvm/trunk/include/llvm/CodeGen/SelectionDAGNodes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/SelectionDAGNodes.h?rev=139221&r1=139220&r2=139221&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/SelectionDAGNodes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/SelectionDAGNodes.h Tue Sep  6 21:23:42 2011
@@ -998,8 +998,10 @@
     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:

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp?rev=139221&r1=139220&r2=139221&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp Tue Sep  6 21:23:42 2011
@@ -3840,6 +3840,8 @@
   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 @@
     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 @@
     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 =

Modified: llvm/trunk/test/CodeGen/ARM/atomic-load-store.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/atomic-load-store.ll?rev=139221&r1=139220&r2=139221&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/atomic-load-store.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/atomic-load-store.ll Tue Sep  6 21:23:42 2011
@@ -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