From 85d3f1ee8f109c0f180050020ef9d7c233f782e5 Mon Sep 17 00:00:00 2001
From: Francis Visoiu Mistrih <francisvm@yahoo.com>
Date: Tue, 30 Oct 2018 12:07:18 +0000
Subject: [PATCH] [llc] Error out when -print-machineinstrs is used with an
 unknown pass

We used to assert instead of reporting an error.

PR39494

llvm-svn: 345589
---
 llvm/lib/CodeGen/TargetPassConfig.cpp         | 20 ++++++++++---------
 .../CodeGen/X86/llc-print-machineinstrs.mir   | 12 +++++++++++
 2 files changed, 23 insertions(+), 9 deletions(-)
 create mode 100644 llvm/test/CodeGen/X86/llc-print-machineinstrs.mir

diff --git a/llvm/lib/CodeGen/TargetPassConfig.cpp b/llvm/lib/CodeGen/TargetPassConfig.cpp
index a3b24d1cd664..6a9c3c05f037 100644
--- a/llvm/lib/CodeGen/TargetPassConfig.cpp
+++ b/llvm/lib/CodeGen/TargetPassConfig.cpp
@@ -806,15 +806,17 @@ void TargetPassConfig::addMachinePasses() {
   AddingMachinePasses = true;
 
   // Insert a machine instr printer pass after the specified pass.
-  if (!StringRef(PrintMachineInstrs.getValue()).equals("") &&
-      !StringRef(PrintMachineInstrs.getValue()).equals("option-unspecified")) {
-    const PassRegistry *PR = PassRegistry::getPassRegistry();
-    const PassInfo *TPI = PR->getPassInfo(PrintMachineInstrs.getValue());
-    const PassInfo *IPI = PR->getPassInfo(StringRef("machineinstr-printer"));
-    assert (TPI && IPI && "Pass ID not registered!");
-    const char *TID = (const char *)(TPI->getTypeInfo());
-    const char *IID = (const char *)(IPI->getTypeInfo());
-    insertPass(TID, IID);
+  StringRef PrintMachineInstrsPassName = PrintMachineInstrs.getValue();
+  if (!PrintMachineInstrsPassName.equals("") &&
+      !PrintMachineInstrsPassName.equals("option-unspecified")) {
+    if (const PassInfo *TPI = getPassInfo(PrintMachineInstrsPassName)) {
+      const PassRegistry *PR = PassRegistry::getPassRegistry();
+      const PassInfo *IPI = PR->getPassInfo(StringRef("machineinstr-printer"));
+      assert(IPI && "failed to get \"machineinstr-printer\" PassInfo!");
+      const char *TID = (const char *)(TPI->getTypeInfo());
+      const char *IID = (const char *)(IPI->getTypeInfo());
+      insertPass(TID, IID);
+    }
   }
 
   // Print the instruction selected machine code...
diff --git a/llvm/test/CodeGen/X86/llc-print-machineinstrs.mir b/llvm/test/CodeGen/X86/llc-print-machineinstrs.mir
new file mode 100644
index 000000000000..a890840a478a
--- /dev/null
+++ b/llvm/test/CodeGen/X86/llc-print-machineinstrs.mir
@@ -0,0 +1,12 @@
+# Check that -print-machineinstrs doesn't assert when it's passed an unknown pass name.
+# RUN: llc -mtriple=x86_64-- -start-before=greedy -print-machineinstrs=greedy %s -o /dev/null
+# RUN: not llc -mtriple=x86_64-- -start-before=greedy -print-machineinstrs=unknown %s -o /dev/null 2>&1 | FileCheck %s
+# CHECK: LLVM ERROR: "unknown" pass is not registered.
+
+...
+---
+name: fun
+tracksRegLiveness: true
+body: |
+  bb.0:
+    RET 0