maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[X86] Remove dead code from retpoline thunk generation 

Follow-up to r325049

llvm-svn: 325085
This commit is contained in:
Reid Kleckner 2018-02-14 00:24:29 +00:00
parent 293a0556f3
commit 1631ac1696
1 changed files with 0 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
llvm/lib/Target/X86/X86RetpolineThunks.cpp
View File

@ -74,7 +74,6 @@ private:
void createThunkFunction(Module &M, StringRef Name); void createThunkFunction(Module &M, StringRef Name);
void insertRegReturnAddrClobber(MachineBasicBlock &MBB, unsigned Reg); void insertRegReturnAddrClobber(MachineBasicBlock &MBB, unsigned Reg);
void insert32BitPushReturnAddrClobber(MachineBasicBlock &MBB);
void populateThunk(MachineFunction &MF, Optional<unsigned> Reg = None); void populateThunk(MachineFunction &MF, Optional<unsigned> Reg = None);
}; };
@ -225,31 +224,6 @@ void X86RetpolineThunks::insertRegReturnAddrClobber(MachineBasicBlock &MBB,
.addReg(Reg); .addReg(Reg);
} }
void X86RetpolineThunks::insert32BitPushReturnAddrClobber(
MachineBasicBlock &MBB) {
// The instruction sequence we use to replace the return address without
// a scratch register is somewhat complicated:
// # Clear capture_spec from return address.
// addl $4, %esp
// # Top of stack words are: Callee, RA. Exchange Callee and RA.
// pushl 4(%esp) # Push callee
// pushl 4(%esp) # Push RA
// popl 8(%esp) # Pop RA to final RA
// popl (%esp) # Pop callee to next top of stack
// retl # Ret to callee
BuildMI(&MBB, DebugLoc(), TII->get(X86::ADD32ri), X86::ESP)
.addReg(X86::ESP)
.addImm(4);
addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::PUSH32rmm)), X86::ESP,
false, 4);
addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::PUSH32rmm)), X86::ESP,
false, 4);
addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::POP32rmm)), X86::ESP,
false, 8);
addRegOffset(BuildMI(&MBB, DebugLoc(), TII->get(X86::POP32rmm)), X86::ESP,
false, 0);
}
void X86RetpolineThunks::populateThunk(MachineFunction &MF, void X86RetpolineThunks::populateThunk(MachineFunction &MF,
Optional<unsigned> Reg) { Optional<unsigned> Reg) {
// Set MF properties. We never use vregs... // Set MF properties. We never use vregs...