[llvm] r333133 - [DebugInfo] Maintain DI for sunken bitcasts

[Vedant Kumar via llvm-commits]

Author: vedantk
Date: Wed May 23 15:03:48 2018
New Revision: 333133

URL: http://llvm.org/viewvc/llvm-project?rev=333133&view=rev
Log:
[DebugInfo] Maintain DI for sunken bitcasts

When a bitcast is being sunk in -codegenprepare pass, its DI wasn't
copied over to the newly created instruction. This patch fixes that
bug.

Patch by Kareem Ergawy!

Differential Revision: https://reviews.llvm.org/D47282

Added:
    llvm/trunk/test/DebugInfo/sink-bitcast-di.ll
Modified:
    llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp

Modified: llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp?rev=333133&r1=333132&r2=333133&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp (original)
+++ llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp Wed May 23 15:03:48 2018
@@ -1050,6 +1050,7 @@ static bool SinkCast(CastInst *CI) {
       assert(InsertPt != UserBB->end());
       InsertedCast = CastInst::Create(CI->getOpcode(), CI->getOperand(0),
                                       CI->getType(), "", &*InsertPt);
+      InsertedCast->setDebugLoc(CI->getDebugLoc());
     }
 
     // Replace a use of the cast with a use of the new cast.

Added: llvm/trunk/test/DebugInfo/sink-bitcast-di.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/sink-bitcast-di.ll?rev=333133&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/sink-bitcast-di.ll (added)
+++ llvm/trunk/test/DebugInfo/sink-bitcast-di.ll Wed May 23 15:03:48 2018
@@ -0,0 +1,37 @@
+; RUN: opt -S -debugify -codegenprepare < %s | FileCheck %s
+
+target datalayout =
+"e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare void @foo(i32)
+
+declare void @slowpath(i32, i32*)
+
+; Is DI maintained after sinking bitcast?
+define void @test(i1 %cond, i64* %base) {
+; CHECK-LABEL: @test
+entry:
+  %addr = getelementptr inbounds i64, i64* %base, i64 5
+  %casted = bitcast i64* %addr to i32*
+  br i1 %cond, label %if.then, label %fallthrough
+
+if.then:
+; CHECK-LABEL: if.then:
+; CHECK: bitcast i64* %addr to i32*, !dbg ![[castLoc:[0-9]+]]
+  %v1 = load i32, i32* %casted, align 4
+  call void @foo(i32 %v1)
+  %cmp = icmp eq i32 %v1, 0
+  br i1 %cmp, label %rare.1, label %fallthrough
+
+fallthrough:
+  ret void
+
+rare.1:
+; CHECK-LABEL: rare.1:
+; CHECK: bitcast i64* %addr to i32*, !dbg ![[castLoc]]
+  call void @slowpath(i32 %v1, i32* %casted) ;; NOT COLD
+  br label %fallthrough
+}
+
+; CHECK: ![[castLoc]] = !DILocation(line: 2