diff options
| author | Dimitry Andric <dim@FreeBSD.org> | 2017-12-02 12:46:23 +0000 |
|---|---|---|
| committer | Dimitry Andric <dim@FreeBSD.org> | 2017-12-02 12:46:23 +0000 |
| commit | edad5bcb76bf472a1487c0f3dd94a5914213a647 (patch) | |
| tree | 63c3f98843d0debbfd390005cf8e05250cd3fe28 /lib/Target/Mips/MipsFrameLowering.cpp | |
| parent | 0bc1bd0d3931803dc6a26d35758f93527359bcdb (diff) | |
Vendor import of llvm release_50 branch r319231:vendor/llvm/llvm-release_50-r319231
Notes
svn path=/vendor/llvm/dist/; revision=326460
svn path=/vendor/llvm/llvm-release_50-r319231/; revision=326461; tag=vendor/llvm/llvm-release_50-r319231
Diffstat (limited to 'lib/Target/Mips/MipsFrameLowering.cpp')
| -rw-r--r-- | lib/Target/Mips/MipsFrameLowering.cpp | 35 |
1 files changed, 14 insertions, 21 deletions
diff --git a/lib/Target/Mips/MipsFrameLowering.cpp b/lib/Target/Mips/MipsFrameLowering.cpp index ef05166503b2..27a85970da6f 100644 --- a/lib/Target/Mips/MipsFrameLowering.cpp +++ b/lib/Target/Mips/MipsFrameLowering.cpp @@ -107,38 +107,31 @@ bool MipsFrameLowering::hasBP(const MachineFunction &MF) const { return MFI.hasVarSizedObjects() && TRI->needsStackRealignment(MF); } +// Estimate the size of the stack, including the incoming arguments. We need to +// account for register spills, local objects, reserved call frame and incoming +// arguments. This is required to determine the largest possible positive offset +// from $sp so that it can be determined if an emergency spill slot for stack +// addresses is required. uint64_t MipsFrameLowering::estimateStackSize(const MachineFunction &MF) const { const MachineFrameInfo &MFI = MF.getFrameInfo(); const TargetRegisterInfo &TRI = *STI.getRegisterInfo(); - int64_t Offset = 0; + int64_t Size = 0; - // Iterate over fixed sized objects. + // Iterate over fixed sized objects which are incoming arguments. for (int I = MFI.getObjectIndexBegin(); I != 0; ++I) - Offset = std::max(Offset, -MFI.getObjectOffset(I)); + if (MFI.getObjectOffset(I) > 0) + Size += MFI.getObjectSize(I); // Conservatively assume all callee-saved registers will be saved. for (const MCPhysReg *R = TRI.getCalleeSavedRegs(&MF); *R; ++R) { - unsigned Size = TRI.getSpillSize(*TRI.getMinimalPhysRegClass(*R)); - Offset = alignTo(Offset + Size, Size); + unsigned RegSize = TRI.getSpillSize(*TRI.getMinimalPhysRegClass(*R)); + Size = alignTo(Size + RegSize, RegSize); } - unsigned MaxAlign = MFI.getMaxAlignment(); - - // Check that MaxAlign is not zero if there is a stack object that is not a - // callee-saved spill. - assert(!MFI.getObjectIndexEnd() || MaxAlign); - - // Iterate over other objects. - for (unsigned I = 0, E = MFI.getObjectIndexEnd(); I != E; ++I) - Offset = alignTo(Offset + MFI.getObjectSize(I), MaxAlign); - - // Call frame. - if (MFI.adjustsStack() && hasReservedCallFrame(MF)) - Offset = alignTo(Offset + MFI.getMaxCallFrameSize(), - std::max(MaxAlign, getStackAlignment())); - - return alignTo(Offset, getStackAlignment()); + // Get the size of the rest of the frame objects and any possible reserved + // call frame, accounting for alignment. + return Size + MFI.estimateStackSize(MF); } // Eliminate ADJCALLSTACKDOWN, ADJCALLSTACKUP pseudo instructions |