[llvm] 8c2d2d9 - Preserve DbgLoc when DeadArgumentElimination rewrites a 'ret'.

[Paul Robinson via llvm-commits]

Author: Paul Robinson
Date: 2020-05-29T10:00:33-07:00
New Revision: 8c2d2d971b2a221786e29380666d9900adeaee6a

URL: https://github.com/llvm/llvm-project/commit/8c2d2d971b2a221786e29380666d9900adeaee6a
DIFF: https://github.com/llvm/llvm-project/commit/8c2d2d971b2a221786e29380666d9900adeaee6a.diff

LOG: Preserve DbgLoc when DeadArgumentElimination rewrites a 'ret'.

Fixes PR46002.

Added: 
    

Modified: 
    llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
    llvm/test/Transforms/DeadArgElim/dbginfo-preserve-dbgloc.ll

Removed: 
    


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diff  --git a/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp b/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
index 5dc1a6ff6327..00fcba40c36f 100644
--- a/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
+++ b/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
@@ -1056,7 +1056,8 @@ bool DeadArgumentEliminationPass::RemoveDeadStuffFromFunction(Function *F) {
         }
         // Replace the return instruction with one returning the new return
         // value (possibly 0 if we became void).
-        ReturnInst::Create(F->getContext(), RetVal, RI);
+        auto *NewRet = ReturnInst::Create(F->getContext(), RetVal, RI);
+        NewRet->setDebugLoc(RI->getDebugLoc());
         BB.getInstList().erase(RI);
       }
 

diff  --git a/llvm/test/Transforms/DeadArgElim/dbginfo-preserve-dbgloc.ll b/llvm/test/Transforms/DeadArgElim/dbginfo-preserve-dbgloc.ll
index de5082d99bf5..ab7645ecf610 100644
--- a/llvm/test/Transforms/DeadArgElim/dbginfo-preserve-dbgloc.ll
+++ b/llvm/test/Transforms/DeadArgElim/dbginfo-preserve-dbgloc.ll
@@ -63,6 +63,7 @@ if.end3:                                          ; preds = %if.end
 
 cleanup:                                          ; preds = %if.end3, %if.then2, %if.then
   %retval.0 = phi i1 [ false, %if.then2 ], [ true, %if.end3 ], [ false, %if.then ]
+; CHECK: ret void, !dbg
   ret i1 %retval.0, !dbg !56
 }