[llvm] 44ce487 - [TableGen] Emit more helpful error messages on empty type set

[Alex Richardson via llvm-commits]

Author: Alex Richardson
Date: 2021-03-31T09:24:03+01:00
New Revision: 44ce487bfe8badc3e3718e7cc81c289540e6725d

URL: https://github.com/llvm/llvm-project/commit/44ce487bfe8badc3e3718e7cc81c289540e6725d
DIFF: https://github.com/llvm/llvm-project/commit/44ce487bfe8badc3e3718e7cc81c289540e6725d.diff

LOG: [TableGen] Emit more helpful error messages on empty type set

I have seen this error quite frequently in our out-of-tree CHERI backends
and the lack of location information sometimes makes it quite difficult
to track down the actual source of the error.
This patch changes the llvm_unreachable() to a PrintFatalError() so that
tablegen prints a stack of source locations.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D99468

Added: 
    

Modified: 
    llvm/utils/TableGen/CodeGenDAGPatterns.cpp

Removed: 
    


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diff  --git a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
index 1b996f0200511..ce6e090ee584d 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -846,7 +846,11 @@ TypeInfer::ValidateOnExit::~ValidateOnExit() {
               "(use -print-records with llvm-tblgen to see all "
               "expanded records).\n";
     Infer.TP.dump();
-    llvm_unreachable(nullptr);
+    dbgs() << "Generated from record:\n";
+    Infer.TP.getRecord()->dump();
+    PrintFatalError(Infer.TP.getRecord()->getLoc(),
+                    "Type set is empty for each HW mode in '" +
+                        Infer.TP.getRecord()->getName() + "'");
   }
 }
 #endif