Make %EFLAGS unallocatable.

No CCR virtual registers should exist, and %EFLAGS is used in ways that can
surprise RegAllocFast.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112650 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2010-08-31 21:51:07 +00:00
parent f14a648d80
commit 63b1dbaadd

View File

@ -833,4 +833,15 @@ def VR256 : RegisterClass<"X86", [v32i8, v8i32, v4i64, v8f32, v4f64], 256,
// Status flags registers.
def CCR : RegisterClass<"X86", [i32], 32, [EFLAGS]> {
let CopyCost = -1; // Don't allow copying of status registers.
// EFLAGS is not allocatable.
let MethodProtos = [{
iterator allocation_order_end(const MachineFunction &MF) const;
}];
let MethodBodies = [{
CCRClass::iterator
CCRClass::allocation_order_end(const MachineFunction &MF) const {
return allocation_order_begin(MF);
}
}];
}