commit 1f8a99a9ae8c22ac1c90ee623d132ca0ee4bc0f5
author Duncan P. N. Exon Smith <dexonsmith@apple.com> Sat Jun 27 00:38:26 2015 +0000
committer Duncan P. N. Exon Smith <dexonsmith@apple.com> Sat Jun 27 00:38:26 2015 +0000
tree e7acd4a5fa945bc284cf88492a121fbd65e88c83
parent ba4c8b50043a33eefac3d150d82e4fd5dfeba7dd

IR: Expose ModuleSlotTracker in Value::print()

Allow callers of `Value::print()` and `Metadata::print()` to pass in a
`ModuleSlotTracker`.  This allows them to pay only once for calculating
module-level slots (such as Metadata).

This is related to PR23865, where there was a huge cost for
`MachineFunction::print()`.  Although I don't have a *particular* user
in mind for this new code, I have hit big slowdowns before when running
`opt -debug`, and I think this will be useful.  Going forward, if
someone hits a big slowdown with `print()` statements, they can create a
`ModuleSlotTracker` and send it through.  Similarly, adding support to
`Value::dump()` and `Metadata::dump()` should be trivial.

I added unit tests to be sure the `print()` functions actually behave
the same way with and without the slot tracker.

llvm-svn: 240867

llvm/unittests/IR/MetadataTest.cpp

diff --git a/llvm/unittests/IR/MetadataTest.cpp b/llvm/unittests/IR/MetadataTest.cpp
index b255ba8..c1da068 100644
--- a/llvm/unittests/IR/MetadataTest.cpp
+++ b/llvm/unittests/IR/MetadataTest.cpp
@@ -16,6 +16,7 @@
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Module.h"
+#include "llvm/IR/ModuleSlotTracker.h"
 #include "llvm/IR/Type.h"
 #include "llvm/IR/Verifier.h"
 #include "llvm/Support/raw_ostream.h"
@@ -356,6 +357,10 @@
 
   EXPECT_PRINTER_EQ("!0 = distinct !{}", N0->print(OS, &M));
   EXPECT_PRINTER_EQ("!1 = distinct !{}", N1->print(OS, &M));
+
+  ModuleSlotTracker MST(&M);
+  EXPECT_PRINTER_EQ("!0 = distinct !{}", N0->print(OS, MST));
+  EXPECT_PRINTER_EQ("!1 = distinct !{}", N1->print(OS, MST));
 }
 
 TEST_F(MDNodeTest, PrintFromMetadataAsValue) {
@@ -384,6 +389,14 @@
   EXPECT_PRINTER_EQ("!1", MAV1->printAsOperand(OS, false));
   EXPECT_PRINTER_EQ("metadata !0", MAV0->printAsOperand(OS, true));
   EXPECT_PRINTER_EQ("metadata !1", MAV1->printAsOperand(OS, true));
+
+  ModuleSlotTracker MST(&M);
+  EXPECT_PRINTER_EQ("!0 = distinct !{}", MAV0->print(OS, MST));
+  EXPECT_PRINTER_EQ("!1 = distinct !{}", MAV1->print(OS, MST));
+  EXPECT_PRINTER_EQ("!0", MAV0->printAsOperand(OS, false, MST));
+  EXPECT_PRINTER_EQ("!1", MAV1->printAsOperand(OS, false, MST));
+  EXPECT_PRINTER_EQ("metadata !0", MAV0->printAsOperand(OS, true, MST));
+  EXPECT_PRINTER_EQ("metadata !1", MAV1->printAsOperand(OS, true, MST));
 }
 #undef EXPECT_PRINTER_EQ