CodeGen: Remove pipeline dependencies on StackProtector; NFC

PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.

PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.

This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.

Patch by Stephen Crane <sjc@immunant.com>

Differential Revision: https://reviews.llvm.org/D49256

llvm-svn: 336929

1 files changed, 11 insertions, 10 deletions

diff --git a/llvm/lib/CodeGen/StackColoring.cpp b/llvm/lib/CodeGen/StackColoring.cpp
index 0bd941e64aa..f9d1eaf0307 100644
--- a/llvm/lib/CodeGen/StackColoring.cpp
+++ b/llvm/lib/CodeGen/StackColoring.cpp
@@ -39,7 +39,6 @@
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/SelectionDAGNodes.h"
 #include "llvm/CodeGen/SlotIndexes.h"
-#include "llvm/CodeGen/StackProtector.h"
 #include "llvm/CodeGen/TargetOpcodes.h"
 #include "llvm/CodeGen/WinEHFuncInfo.h"
 #include "llvm/Config/llvm-config.h"
@@ -423,9 +422,6 @@ class StackColoring : public MachineFunctionPass {
   /// SlotIndex analysis object.
   SlotIndexes *Indexes;
 
-  /// The stack protector object.
-  StackProtector *SP;
-
   /// The list of lifetime markers found. These markers are to be removed
   /// once the coloring is done.
   SmallVector<MachineInstr*, 8> Markers;
@@ -524,13 +520,11 @@ char &llvm::StackColoringID = StackColoring::ID;
 INITIALIZE_PASS_BEGIN(StackColoring, DEBUG_TYPE,
                       "Merge disjoint stack slots", false, false)
 INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
-INITIALIZE_PASS_DEPENDENCY(StackProtector)
 INITIALIZE_PASS_END(StackColoring, DEBUG_TYPE,
                     "Merge disjoint stack slots", false, false)
 
 void StackColoring::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<SlotIndexes>();
-  AU.addRequired<StackProtector>();
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
@@ -936,9 +930,17 @@ void StackColoring::remapInstructions(DenseMap<int, int> &SlotRemap) {
     MergedAllocas.insert(From);
     MergedAllocas.insert(To);
 
-    // Allow the stack protector to adjust its value map to account for the
-    // upcoming replacement.
-    SP->adjustForColoring(From, To);
+    // Transfer the stack protector layout tag, but make sure that SSPLK_AddrOf
+    // does not overwrite SSPLK_SmallArray or SSPLK_LargeArray, and make sure
+    // that SSPLK_SmallArray does not overwrite SSPLK_LargeArray.
+    MachineFrameInfo::SSPLayoutKind FromKind
+        = MFI->getObjectSSPLayout(SI.first);
+    MachineFrameInfo::SSPLayoutKind ToKind = MFI->getObjectSSPLayout(SI.second);
+    if (FromKind != MachineFrameInfo::SSPLK_None &&
+        (ToKind == MachineFrameInfo::SSPLK_None ||
+         (ToKind != MachineFrameInfo::SSPLK_LargeArray &&
+          FromKind != MachineFrameInfo::SSPLK_AddrOf)))
+      MFI->setObjectSSPLayout(SI.second, FromKind);
 
     // The new alloca might not be valid in a llvm.dbg.declare for this
     // variable, so undef out the use to make the verifier happy.
@@ -1139,7 +1141,6 @@ bool StackColoring::runOnMachineFunction(MachineFunction &Func) {
   MF = &Func;
   MFI = &MF->getFrameInfo();
   Indexes = &getAnalysis<SlotIndexes>();
-  SP = &getAnalysis<StackProtector>();
   BlockLiveness.clear();
   BasicBlocks.clear();
   BasicBlockNumbering.clear();