PNaCl: Impl the other atomicrmw operations: nand, max, min, umax, and umin.

lib/Analysis/NaCl/PNaClSimplificationAnalyses.cpp

Index: lib/Analysis/NaCl/PNaClSimplificationAnalyses.cpp
diff --git a/lib/Analysis/NaCl/PNaClSimplificationAnalyses.cpp b/lib/Analysis/NaCl/PNaClSimplificationAnalyses.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..7dda08fbba56f68c317b66867204bcdeb70c857e
--- /dev/null
+++ b/lib/Analysis/NaCl/PNaClSimplificationAnalyses.cpp
@@ -0,0 +1,67 @@
+//===- llvm/Analysis/NaCl/SimplificationAnalyses.cpp ------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file houses implementations of the analysis passes used by the PNaCl IR
+// simplification passes to remove extra passes over modules while progressive
+// simplifying the IR, allowing them direct access to what each pass needs to
+// expand.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/NaCl/PNaClSimplificationAnalyses.h"
+#include "llvm/IR/InstIterator.h"
+
+using namespace llvm;
+
+AtomicInfo::AtomicInfo(Function &F) {
+  for (Instruction &I : inst_range(F)) {
+    if (AtomicCmpXchgInst *AI = dyn_cast<AtomicCmpXchgInst>(&I)) {
+      CmpXchgs.push_back(AI);
+    } else if (LoadInst *LI = dyn_cast<LoadInst>(&I)) {
+      if (!LI->isSimple()) {
+        Loads.push_back(LI);
+      }
+    } else if (StoreInst *SI = dyn_cast<StoreInst>(&I)) {
+      if (!SI->isSimple()) {
+        Stores.push_back(SI);
+      }
+    } else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(&I)) {
+      RMWs.push_back(RMWI);
+      switch (RMWI->getOperation()) {
+      default:
+        NeedsAtomicExpand = true;

[JF, 2015/07/27 19:49:28]

Don't leave a fallthrough here, usual LLVM style tries to avoid it (or points
out where it's used when necessary) because it's easier to read.

[Richard Diamond, 2015/07/30 11:47:08]

That wasn't intended. I think Rust's lack of fall through got to me. Fixed.

+      case AtomicRMWInst::Add:
+      case AtomicRMWInst::Sub:
+      case AtomicRMWInst::And:
+      case AtomicRMWInst::Or:
+      case AtomicRMWInst::Xor:
+      case AtomicRMWInst::Xchg:
+        continue;
+      }
+    } else if (FenceInst *FI = dyn_cast<FenceInst>(&I)) {
+      Fences.push_back(FI);
+    }
+  }
+}
+
+char AtomicAnalysis::PassID;
+
+INITIALIZE_PASS(AtomicAnalysisWrapperPass, "pnacl-atomic-analysis",
+                "Find atomic instruction to expand", true, true)
+char AtomicAnalysisWrapperPass::ID = 0;
+
+bool AtomicAnalysisWrapperPass::runOnFunction(Function &F) {
+  releaseMemory();
+  Info = std::move(AtomicInfo(F));
+  return false;
+}
+void AtomicAnalysisWrapperPass::releaseMemory() { Info.releaseMemory(); }
+void AtomicAnalysisWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+}