Reapply "[X86] Correct 32-bit immediate assertion and fix 64-bit lowering for huge frame offsets" (#152239)

The first commit is identical to
69bec0afbb8f2aa0021d18ea38768360b16583a9.

The second commit fixes the instruction verification failures by
replacing the erroneous instruction with a trap after the error is
reported and adds `-verify-machineinstrs` to the tests added in the
original PR to catch the issue sooner.

After that change, all tests pass with both
`LLVM_ENABLE_EXPENSIVE_CHECKS={On,Off}`.

cc @RKSimon @e-kud @phoebewang @arsenm as reviewers on the original PR

1 files changed, 10 insertions, 1 deletions

diff --git a/llvm/lib/Target/X86/X86FrameLowering.cpp b/llvm/lib/Target/X86/X86FrameLowering.cpp
index 95ed590..cba7843 100644
--- a/llvm/lib/Target/X86/X86FrameLowering.cpp
+++ b/llvm/lib/Target/X86/X86FrameLowering.cpp
@@ -24,6 +24,7 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/RegisterScavenging.h"
 #include "llvm/CodeGen/WinEHFuncInfo.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/EHPersonalities.h"
@@ -2678,7 +2679,7 @@ StackOffset X86FrameLowering::getFrameIndexReference(const MachineFunction &MF,
   // object.
   // We need to factor in additional offsets applied during the prologue to the
   // frame, base, and stack pointer depending on which is used.
-  int Offset = MFI.getObjectOffset(FI) - getOffsetOfLocalArea();
+  int64_t Offset = MFI.getObjectOffset(FI) - getOffsetOfLocalArea();
   const X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
   unsigned CSSize = X86FI->getCalleeSavedFrameSize();
   uint64_t StackSize = MFI.getStackSize();
@@ -4212,6 +4213,14 @@ void X86FrameLowering::processFunctionBeforeFrameFinalized(
   // emitPrologue if it gets called and emits CFI.
   MF.setHasWinCFI(false);
 
+  MachineFrameInfo &MFI = MF.getFrameInfo();
+  // If the frame is big enough that we might need to scavenge a register to
+  // handle huge offsets, reserve a stack slot for that now.
+  if (!isInt<32>(MFI.estimateStackSize(MF))) {
+    int FI = MFI.CreateStackObject(SlotSize, Align(SlotSize), false);
+    RS->addScavengingFrameIndex(FI);
+  }
+
   // If we are using Windows x64 CFI, ensure that the stack is always 8 byte
   // aligned. The format doesn't support misaligned stack adjustments.
   if (MF.getTarget().getMCAsmInfo()->usesWindowsCFI())