[LegacyPassManager] Remove TargetMachine constructors

This provides a new way to access the TargetMachine through
TargetPassConfig, as a dependency.

The patterns replaced here are:

* Passes handling a null TargetMachine call
  `getAnalysisIfAvailable<TargetPassConfig>`.

* Passes not handling a null TargetMachine
  `addRequired<TargetPassConfig>` and call
  `getAnalysis<TargetPassConfig>`.

* MachineFunctionPasses now use MF.getTarget().

* Remove all the TargetMachine constructors.
* Remove INITIALIZE_TM_PASS.

This fixes a crash when running `llc -start-before prologepilog`.

PEI needs StackProtector, which gets constructed without a TargetMachine
by the pass manager. The StackProtector pass doesn't handle the case
where there is no TargetMachine, so it segfaults.

Related to PR30324.

Differential Revision: https://reviews.llvm.org/D33222

llvm-svn: 303360

1 files changed, 10 insertions, 12 deletions

diff --git a/llvm/lib/CodeGen/SafeStack.cpp b/llvm/lib/CodeGen/SafeStack.cpp
index 08b3d34..2771fdb 100644
--- a/llvm/lib/CodeGen/SafeStack.cpp
+++ b/llvm/lib/CodeGen/SafeStack.cpp
@@ -24,6 +24,7 @@
 #include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/Analysis/ScalarEvolutionExpressions.h"
 #include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/TargetPassConfig.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DIBuilder.h"
 #include "llvm/IR/DataLayout.h"
@@ -767,13 +768,12 @@ class SafeStackLegacyPass : public FunctionPass {
 
 public:
   static char ID; // Pass identification, replacement for typeid..
-  SafeStackLegacyPass(const TargetMachine *TM) : FunctionPass(ID), TM(TM) {
+  SafeStackLegacyPass() : FunctionPass(ID), TM(nullptr) {
     initializeSafeStackLegacyPassPass(*PassRegistry::getPassRegistry());
   }
 
-  SafeStackLegacyPass() : SafeStackLegacyPass(nullptr) {}
-
   void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.addRequired<TargetPassConfig>();
     AU.addRequired<TargetLibraryInfoWrapperPass>();
     AU.addRequired<AssumptionCacheTracker>();
   }
@@ -793,8 +793,7 @@ public:
       return false;
     }
 
-    if (!TM)
-      report_fatal_error("Target machine is required");
+    TM = &getAnalysis<TargetPassConfig>().getTM<TargetMachine>();
     auto *TL = TM->getSubtargetImpl(F)->getTargetLowering();
     if (!TL)
       report_fatal_error("TargetLowering instance is required");
@@ -821,11 +820,10 @@ public:
 } // anonymous namespace
 
 char SafeStackLegacyPass::ID = 0;
-INITIALIZE_TM_PASS_BEGIN(SafeStackLegacyPass, "safe-stack",
-                         "Safe Stack instrumentation pass", false, false)
-INITIALIZE_TM_PASS_END(SafeStackLegacyPass, "safe-stack",
-                       "Safe Stack instrumentation pass", false, false)
+INITIALIZE_PASS_BEGIN(SafeStackLegacyPass, "safe-stack",
+                      "Safe Stack instrumentation pass", false, false)
+INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
+INITIALIZE_PASS_END(SafeStackLegacyPass, "safe-stack",
+                    "Safe Stack instrumentation pass", false, false)
 
-FunctionPass *llvm::createSafeStackPass(const llvm::TargetMachine *TM) {
-  return new SafeStackLegacyPass(TM);
-}
+FunctionPass *llvm::createSafeStackPass() { return new SafeStackLegacyPass(); }