[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, 12 insertions, 10 deletions

diff --git a/llvm/lib/CodeGen/AtomicExpandPass.cpp b/llvm/lib/CodeGen/AtomicExpandPass.cpp
index 17e6be05eb4..984973cf3a3 100644
--- a/llvm/lib/CodeGen/AtomicExpandPass.cpp
+++ b/llvm/lib/CodeGen/AtomicExpandPass.cpp
@@ -17,6 +17,7 @@
 
 #include "llvm/CodeGen/AtomicExpandUtils.h"
 #include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/TargetPassConfig.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/InstIterator.h"
@@ -35,12 +36,10 @@ using namespace llvm;
 
 namespace {
   class AtomicExpand: public FunctionPass {
-    const TargetMachine *TM;
     const TargetLowering *TLI;
   public:
     static char ID; // Pass identification, replacement for typeid
-    explicit AtomicExpand(const TargetMachine *TM = nullptr)
-      : FunctionPass(ID), TM(TM), TLI(nullptr) {
+    AtomicExpand() : FunctionPass(ID), TLI(nullptr) {
       initializeAtomicExpandPass(*PassRegistry::getPassRegistry());
     }
 
@@ -97,12 +96,10 @@ namespace {
 
 char AtomicExpand::ID = 0;
 char &llvm::AtomicExpandID = AtomicExpand::ID;
-INITIALIZE_TM_PASS(AtomicExpand, "atomic-expand", "Expand Atomic instructions",
-                   false, false)
+INITIALIZE_PASS(AtomicExpand, "atomic-expand", "Expand Atomic instructions",
+                false, false)
 
-FunctionPass *llvm::createAtomicExpandPass(const TargetMachine *TM) {
-  return new AtomicExpand(TM);
-}
+FunctionPass *llvm::createAtomicExpandPass() { return new AtomicExpand(); }
 
 namespace {
 // Helper functions to retrieve the size of atomic instructions.
@@ -172,9 +169,14 @@ bool atomicSizeSupported(const TargetLowering *TLI, Inst *I) {
 } // end anonymous namespace
 
 bool AtomicExpand::runOnFunction(Function &F) {
-  if (!TM || !TM->getSubtargetImpl(F)->enableAtomicExpand())
+  auto *TPC = getAnalysisIfAvailable<TargetPassConfig>();
+  if (!TPC)
+    return false;
+
+  auto &TM = TPC->getTM<TargetMachine>();
+  if (!TM.getSubtargetImpl(F)->enableAtomicExpand())
     return false;
-  TLI = TM->getSubtargetImpl(F)->getTargetLowering();
+  TLI = TM.getSubtargetImpl(F)->getTargetLowering();
 
   SmallVector<Instruction *, 1> AtomicInsts;