[NFC][LICM] Minor improvements to debug output

Added a utility function in Value class to print block name and use
block labels for unnamed blocks.
Changed LICM to call this function in its debug output.

Patch by Xiaoqing Wu <xiaoqing_wu@apple.com>

Differential Revision: https://reviews.llvm.org/D93577

1 files changed, 12 insertions, 0 deletions

diff --git a/llvm/lib/IR/Value.cpp b/llvm/lib/IR/Value.cpp
index 51a84b6..572f37a 100644
--- a/llvm/lib/IR/Value.cpp
+++ b/llvm/lib/IR/Value.cpp
@@ -430,6 +430,18 @@ void Value::takeName(Value *V) {
     ST->reinsertValue(this);
 }
 
+#ifndef NDEBUG
+std::string Value::getNameOrAsOperand() const {
+  if (!getName().empty())
+    return std::string(getName());
+
+  std::string BBName;
+  raw_string_ostream OS(BBName);
+  printAsOperand(OS, false);
+  return OS.str();
+}
+#endif
+
 void Value::assertModuleIsMaterializedImpl() const {
 #ifndef NDEBUG
   const GlobalValue *GV = dyn_cast<GlobalValue>(this);