From 6a45370c0f92b1ea1eac9fd2b912d2f326719a9b Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Wed, 7 Sep 2011 02:23:42 +0000 Subject: [PATCH] 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.) llvm-svn: 139221 --- include/llvm/CodeGen/SelectionDAGNodes.h | 6 ++++-- lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 19 +++++++++++++++++-- test/CodeGen/ARM/atomic-load-store.ll | 2 +- 3 files changed, 22 insertions(+), 5 deletions(-) diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h index 2ecdc9a48c4..6c7be69b4d2 100644 --- 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 5f5a880edfa..19da986fe8e 100644 --- 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 81c828485e6..4d6b403ce94 100644 --- 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