[WebAssembly] Add an option to make get_local/set_local explicit.

This patch adds a pass, controlled by an option and off by default for
now, for making implicit get_local/set_local explicit. This simplifies
emitting wasm with MC.

Differential Revision: https://reviews.llvm.org/D25836

llvm-svn: 285009

1 files changed, 71 insertions, 0 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyUtilities.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyUtilities.cpp
new file mode 100644
index 00000000000..a0049c147d2
--- /dev/null
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyUtilities.cpp
@@ -0,0 +1,71 @@
+//===-- WebAssemblyUtilities.cpp - WebAssembly Utility Functions ----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file implements several utility functions for WebAssembly.
+///
+//===----------------------------------------------------------------------===//
+
+#include "WebAssemblyUtilities.h"
+#include "WebAssemblyMachineFunctionInfo.h"
+#include "llvm/CodeGen/MachineInstr.h"
+using namespace llvm;
+
+bool WebAssembly::isArgument(const MachineInstr &MI) {
+  switch (MI.getOpcode()) {
+  case WebAssembly::ARGUMENT_I32:
+  case WebAssembly::ARGUMENT_I64:
+  case WebAssembly::ARGUMENT_F32:
+  case WebAssembly::ARGUMENT_F64:
+  case WebAssembly::ARGUMENT_v16i8:
+  case WebAssembly::ARGUMENT_v8i16:
+  case WebAssembly::ARGUMENT_v4i32:
+  case WebAssembly::ARGUMENT_v4f32:
+    return true;
+  default:
+    return false;
+  }
+}
+
+bool WebAssembly::isCopy(const MachineInstr &MI) {
+  switch (MI.getOpcode()) {
+  case WebAssembly::COPY_I32:
+  case WebAssembly::COPY_I64:
+  case WebAssembly::COPY_F32:
+  case WebAssembly::COPY_F64:
+    return true;
+  default:
+    return false;
+  }
+}
+
+bool WebAssembly::isTee(const MachineInstr &MI) {
+  switch (MI.getOpcode()) {
+  case WebAssembly::TEE_I32:
+  case WebAssembly::TEE_I64:
+  case WebAssembly::TEE_F32:
+  case WebAssembly::TEE_F64:
+    return true;
+  default:
+    return false;
+  }
+}
+
+/// Test whether MI is a child of some other node in an expression tree.
+bool WebAssembly::isChild(const MachineInstr &MI,
+                          const WebAssemblyFunctionInfo &MFI) {
+  if (MI.getNumOperands() == 0)
+    return false;
+  const MachineOperand &MO = MI.getOperand(0);
+  if (!MO.isReg() || MO.isImplicit() || !MO.isDef())
+    return false;
+  unsigned Reg = MO.getReg();
+  return TargetRegisterInfo::isVirtualRegister(Reg) &&
+         MFI.isVRegStackified(Reg);
+}