[NewPM][PassInstrumentation] IR printing support for (Thin)LTO

Summary: IR printing has not been correctly supported with (Thin)LTO if the new pass manager is enabled. Previously we only get outputs from backend(codegen) passes, as they are still under legacy pass manager even when the new pass manager is enabled. This patch addresses the issue and enables IR printing for optimization passes with new pass manager + (Thin)LTO setting.

Reviewers: fedor.sergeev, philip.pfaffe

Subscribers: mehdi_amini, inglorion, hiraditya, steven_wu, dexonsmith, dang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66253

llvm-svn: 369024

Author: taewookoh

llvm/lib/LTO/LTOBackend.cpp

@@ -28,6 +28,7 @@
 #include "llvm/MC/SubtargetFeature.h"
 #include "llvm/Object/ModuleSymbolTable.h"
 #include "llvm/Passes/PassBuilder.h"
+#include "llvm/Passes/StandardInstrumentations.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/MemoryBuffer.h"
@@ -165,7 +166,10 @@ static void runNewPMPasses(Config &Conf, Module &Mod, TargetMachine *TM,
                         PGOOptions::IRUse, PGOOptions::CSIRUse);
   }
 
-  PassBuilder PB(TM, PipelineTuningOptions(), PGOOpt);
+  PassInstrumentationCallbacks PIC;
+  StandardInstrumentations SI;
+  SI.registerCallbacks(PIC);
+  PassBuilder PB(TM, PipelineTuningOptions(),PGOOpt, &PIC);
   AAManager AA;
 
   // Parse a custom AA pipeline if asked to.

llvm/test/ThinLTO/X86/printer.ll

@@ -0,0 +1,12 @@
+; RUN: llvm-as %s -o %t.bc
+; RUN: llvm-lto2 run -r=%t.bc,foo,pxl -use-new-pm --print-before-all %t.bc -o - 2>&1 | FileCheck %s --check-prefix=CHECK-BEFORE
+; RUN: llvm-lto2 run -r=%t.bc,foo,pxl -use-new-pm --print-after-all %t.bc -o - 2>&1 | FileCheck %s --check-prefix=CHECK-AFTER
+; CHECK-BEFORE: *** IR Dump Before GlobalDCEPass ***
+; CHECK-AFTER: *** IR Dump After GlobalDCEPass ***
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i32 @foo() {
+    ret i32 42
+}