[llvm] 9061eb8 - Revert "Fix frame pointer layout on AArch64 Linux."

[Owen Anderson via llvm-commits]

Author: Owen Anderson
Date: 2020-08-26T17:17:14Z
New Revision: 9061eb8245cc1ae25e8f7865062d1d8e44406994

URL: https://github.com/llvm/llvm-project/commit/9061eb8245cc1ae25e8f7865062d1d8e44406994
DIFF: https://github.com/llvm/llvm-project/commit/9061eb8245cc1ae25e8f7865062d1d8e44406994.diff

LOG: Revert "Fix frame pointer layout on AArch64 Linux."

This broke stage2 of clang-cmake-aarch64-full.

This reverts commit a0aed80b22d1b698b86e0c16109fdfd4d592756f.

Added: 
    

Modified: 
    llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
    llvm/lib/Target/AArch64/AArch64MachineFunctionInfo.h

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
index 687f6a6aa6a3..c6cc6e9e8471 100644
--- a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -1185,26 +1185,7 @@ void AArch64FrameLowering::emitPrologue(MachineFunction &MF,
   // For funclets the FP belongs to the containing function.
   if (!IsFunclet && HasFP) {
     // Only set up FP if we actually need to.
-    int64_t FPOffset;
-
-    // The frame pointer needs to point to the location of the frame record
-    // (x28 and x29) within the callee saved register space.
-    if (isTargetDarwin(MF)) {
-      // On Darwin, these are located at the top of the CSR space.
-      FPOffset = (AFI->getCalleeSavedStackSize() - 16);
-    } else {
-      // On other systems, these are located in the middle of the CSR space,
-      // after the other GPRs and before the FPRs.
-      assert(MFI.isCalleeSavedInfoValid() && "CalleeSavedInfo not calculated");
-      if (MFI.getCalleeSavedInfo().empty()) {
-        FPOffset = 0;
-      } else {
-        FPOffset = AFI->getCalleeSavedStackSize(MFI, [](unsigned Reg) {
-          return AArch64::FPR64RegClass.contains(Reg) ||
-                 AArch64::FPR128RegClass.contains(Reg);
-        });
-      }
-    }
+    int64_t FPOffset = isTargetDarwin(MF) ? (AFI->getCalleeSavedStackSize() - 16) : 0;
 
     if (CombineSPBump)
       FPOffset += AFI->getLocalStackSize();
@@ -1861,16 +1842,8 @@ static StackOffset getFPOffset(const MachineFunction &MF, int64_t ObjectOffset)
 
   unsigned FixedObject =
       getFixedObjectSize(MF, AFI, IsWin64, /*IsFunclet=*/false);
-
-  // Compensate for the position of the frame record within the callee-saved
-  // register space.  On Darwin, this is a fixed offset.  On other systems,
-  // this is determined by the number of callee-saved GPRs, excluding FPRs.
-  unsigned FPAdjust =
-      isTargetDarwin(MF)
-          ? 16
-          : AFI->getCalleeSavedStackSize(MF.getFrameInfo(), [](unsigned Reg) {
-              return AArch64::GPR64RegClass.contains(Reg);
-            });
+  unsigned FPAdjust = isTargetDarwin(MF)
+                        ? 16 : AFI->getCalleeSavedStackSize(MF.getFrameInfo());
   return {ObjectOffset + FixedObject + FPAdjust, MVT::i8};
 }
 

diff  --git a/llvm/lib/Target/AArch64/AArch64MachineFunctionInfo.h b/llvm/lib/Target/AArch64/AArch64MachineFunctionInfo.h
index 8fc41e973afb..84aa53f2bece 100644
--- a/llvm/lib/Target/AArch64/AArch64MachineFunctionInfo.h
+++ b/llvm/lib/Target/AArch64/AArch64MachineFunctionInfo.h
@@ -194,15 +194,9 @@ class AArch64FunctionInfo final : public MachineFunctionInfo {
   // When CalleeSavedStackSize has not been set (for example when
   // some MachineIR pass is run in isolation), then recalculate
   // the CalleeSavedStackSize directly from the CalleeSavedInfo.
-  // RegisterFilter is a predicate to calculate the stack size for
-  // subsets of the callee-saved registers.  It should return true
-  // for registers that should be included in the size calculation,
-  // and false otherwise.
   // Note: This information can only be recalculated after PEI
   // has assigned offsets to the callee save objects.
-  unsigned getCalleeSavedStackSize(
-      const MachineFrameInfo &MFI,
-      llvm::function_ref<bool(unsigned)> RegisterFilter = nullptr) const {
+  unsigned getCalleeSavedStackSize(const MachineFrameInfo &MFI) const {
     bool ValidateCalleeSavedStackSize = false;
 
 #ifndef NDEBUG
@@ -212,24 +206,14 @@ class AArch64FunctionInfo final : public MachineFunctionInfo {
     ValidateCalleeSavedStackSize = HasCalleeSavedStackSize;
 #endif
 
-    if (RegisterFilter || !HasCalleeSavedStackSize ||
-        ValidateCalleeSavedStackSize) {
+    if (!HasCalleeSavedStackSize || ValidateCalleeSavedStackSize) {
       assert(MFI.isCalleeSavedInfoValid() && "CalleeSavedInfo not calculated");
       if (MFI.getCalleeSavedInfo().empty())
         return 0;
 
       int64_t MinOffset = std::numeric_limits<int64_t>::max();
       int64_t MaxOffset = std::numeric_limits<int64_t>::min();
-
-      bool AnyRegistersCounted = false;
       for (const auto &Info : MFI.getCalleeSavedInfo()) {
-        if (RegisterFilter) {
-          unsigned Reg = Info.getReg();
-          if (!RegisterFilter(Reg))
-            continue;
-        }
-
-        AnyRegistersCounted = true;
         int FrameIdx = Info.getFrameIdx();
         if (MFI.getStackID(FrameIdx) != TargetStackID::Default)
           continue;
@@ -237,15 +221,10 @@ class AArch64FunctionInfo final : public MachineFunctionInfo {
         int64_t ObjSize = MFI.getObjectSize(FrameIdx);
         MinOffset = std::min<int64_t>(Offset, MinOffset);
         MaxOffset = std::max<int64_t>(Offset + ObjSize, MaxOffset);
-        AnyRegistersCounted = true;
       }
 
-      if (!AnyRegistersCounted)
-        return 0;
-
       unsigned Size = alignTo(MaxOffset - MinOffset, 16);
-      assert((RegisterFilter || !HasCalleeSavedStackSize ||
-              getCalleeSavedStackSize() == Size) &&
+      assert((!HasCalleeSavedStackSize || getCalleeSavedStackSize() == Size) &&
              "Invalid size calculated for callee saves");
       return Size;
     }