[llvm] 14ad8dc - Don't accidentally create MachineFunctions in mir-debugify/mir-strip-debugify

[Daniel Sanders via llvm-commits]

Author: Daniel Sanders
Date: 2020-04-17T14:28:41-07:00
New Revision: 14ad8dc0761a1e440304a03a1f4828280cf112e2

URL: https://github.com/llvm/llvm-project/commit/14ad8dc0761a1e440304a03a1f4828280cf112e2
DIFF: https://github.com/llvm/llvm-project/commit/14ad8dc0761a1e440304a03a1f4828280cf112e2.diff

LOG: Don't accidentally create MachineFunctions in mir-debugify/mir-strip-debugify

We should only modify existing ones. Previously, we were creating
MachineFunctions for externally-available functions. AFAICT this was benign
in tree but ultimately led to asan bugs in our out of tree target.

Added: 
    

Modified: 
    llvm/lib/CodeGen/MachineDebugify.cpp
    llvm/lib/CodeGen/MachineStripDebug.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/MachineDebugify.cpp b/llvm/lib/CodeGen/MachineDebugify.cpp
index bee9b6346757..bc607cabcc68 100644
--- a/llvm/lib/CodeGen/MachineDebugify.cpp
+++ b/llvm/lib/CodeGen/MachineDebugify.cpp
@@ -27,7 +27,10 @@ using namespace llvm;
 namespace {
 bool applyDebugifyMetadataToMachineFunction(MachineModuleInfo &MMI,
                                             DIBuilder &DIB, Function &F) {
-  MachineFunction &MF = MMI.getOrCreateMachineFunction(F);
+  MachineFunction *MaybeMF = MMI.getMachineFunction(F);
+  if (!MaybeMF)
+    return false;
+  MachineFunction &MF = *MaybeMF;
 
   DISubprogram *SP = F.getSubprogram();
   assert(SP && "IR Debugify just created it?");

diff  --git a/llvm/lib/CodeGen/MachineStripDebug.cpp b/llvm/lib/CodeGen/MachineStripDebug.cpp
index 48b50ceb092a..a1cb12f91275 100644
--- a/llvm/lib/CodeGen/MachineStripDebug.cpp
+++ b/llvm/lib/CodeGen/MachineStripDebug.cpp
@@ -45,7 +45,10 @@ struct StripDebugMachineModule : public ModulePass {
 
     bool Changed = false;
     for (Function &F : M.functions()) {
-      MachineFunction &MF = MMI.getOrCreateMachineFunction(F);
+      MachineFunction *MaybeMF = MMI.getMachineFunction(F);
+      if (!MaybeMF)
+        continue;
+      MachineFunction &MF = *MaybeMF;
       for (MachineBasicBlock &MBB : MF) {
         for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end();
              I != E;) {