Implement llvm.(frame|return)address(0) correctly. They are used by the LLVM JIT, among other
applications
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp
index 6129c74..ed61165 100644
--- a/lib/Target/X86/InstSelectSimple.cpp
+++ b/lib/Target/X86/InstSelectSimple.cpp
@@ -62,6 +62,7 @@
MachineFunction *F; // The function we are compiling into
MachineBasicBlock *BB; // The current MBB we are compiling
int VarArgsFrameIndex; // FrameIndex for start of varargs area
+ int ReturnAddressIndex; // FrameIndex for the return address
std::map<Value*, unsigned> RegMap; // Mapping between Val's and SSA Regs
@@ -86,6 +87,10 @@
BB = &F->front();
+ // Set up a frame object for the return address. This is used by the
+ // llvm.returnaddress & llvm.frameaddress intrinisics.
+ ReturnAddressIndex = F->getFrameInfo()->CreateFixedObject(4, -4);
+
// Copy incoming arguments off of the stack...
LoadArgumentsToVirtualRegs(Fn);
@@ -1157,6 +1162,8 @@
case Intrinsic::va_start:
case Intrinsic::va_copy:
case Intrinsic::va_end:
+ case Intrinsic::returnaddress:
+ case Intrinsic::frameaddress:
case Intrinsic::memcpy:
case Intrinsic::memset:
// We directly implement these intrinsics
@@ -1190,6 +1197,24 @@
return;
case Intrinsic::va_end: return; // Noop on X86
+ case Intrinsic::returnaddress:
+ case Intrinsic::frameaddress:
+ TmpReg1 = getReg(CI);
+ if (cast<Constant>(CI.getOperand(1))->isNullValue()) {
+ if (ID == Intrinsic::returnaddress) {
+ // Just load the return address
+ addFrameReference(BuildMI(BB, X86::MOVmr32, 4, TmpReg1),
+ ReturnAddressIndex);
+ } else {
+ addFrameReference(BuildMI(BB, X86::LEAr32, 4, TmpReg1),
+ ReturnAddressIndex, -4);
+ }
+ } else {
+ // Values other than zero are not implemented yet.
+ BuildMI(BB, X86::MOVir32, 1, TmpReg1).addZImm(0);
+ }
+ return;
+
case Intrinsic::memcpy: {
assert(CI.getNumOperands() == 5 && "Illegal llvm.memcpy call!");
unsigned Align = 1;