[PATCH] D89567: [AsmWriter] Construct SlotTracker with the function

[Kazu Hirata via Phabricator via llvm-commits]

kazu created this revision.
kazu added reviewers: apilipenko, knaumov.
Herald added subscribers: llvm-commits, hiraditya.
Herald added a project: LLVM.
kazu requested review of this revision.

This patch teaches BasicBlock::print to construct an instance of
SlotTracker with the containing function.

Without this patch, we dump:

- IR Dump After LoopInstSimplifyPass ***

; Preheader:

  br label %1

; Loop:
<badref>:                                         ; preds = %1, %0

  br label %1

Note "<badref>" above.  This happens because BasicBlock::print calls:

  SlotTracker SlotTable(this->getModule());

Note that this constructor does not add the contents of functions to
the slot table.  That is, basic blocks are left unnumbered.

This patch fixes the problem by switching to:

  SlotTracker SlotTable(this->getParent());

which does add the contents of the Module and the function,
this->getParent(), to the slot table.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D89567

Files:
  llvm/lib/IR/AsmWriter.cpp
  llvm/test/Other/bb-badref.ll


Index: llvm/test/Other/bb-badref.ll
===================================================================
--- /dev/null
+++ llvm/test/Other/bb-badref.ll
@@ -0,0 +1,14 @@
+; RUN: opt -passes=loop-instsimplify -print-after-all -disable-output -S < %s 2>&1 | FileCheck %s
+
+; loop-instsimplify dumps individual basic blocks as part of a loop,
+; not a function.  Verify that the non-entry basic block is labeled as
+; "1", not "<badref>".
+
+; CHECK-NOT: <badref>
+
+define void @foo() {
+  br label %1
+
+1:
+  br label %1
+}
Index: llvm/lib/IR/AsmWriter.cpp
===================================================================
--- llvm/lib/IR/AsmWriter.cpp
+++ llvm/lib/IR/AsmWriter.cpp
@@ -4406,7 +4406,7 @@
 void BasicBlock::print(raw_ostream &ROS, AssemblyAnnotationWriter *AAW,
                      bool ShouldPreserveUseListOrder,
                      bool IsForDebug) const {
-  SlotTracker SlotTable(this->getModule());
+  SlotTracker SlotTable(this->getParent());
   formatted_raw_ostream OS(ROS);
   AssemblyWriter W(OS, SlotTable, this->getModule(), AAW,
                    IsForDebug,


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