on darwin empty functions need to codegen into something of non-zero length,
otherwise labels get incorrectly merged. We handled this by emitting a
".byte 0", but this isn't correct on thumb/arm targets where the text segment
needs to be a multiple of 2/4 bytes. Handle this by emitting a noop. This
is more gross than it should be because arm/ppc are not fully mc'ized yet.
This fixes rdar://7908505
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102400 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index 4ed7434..9a41a4a 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -27,6 +27,7 @@
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/LiveVariables.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
+#include "llvm/MC/MCInst.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
@@ -3766,3 +3767,9 @@
assert(table && "Cannot change domain");
MI->setDesc(get(table[Domain-1]));
}
+
+/// getNoopForMachoTarget - Return the noop instruction to use for a noop.
+void X86InstrInfo::getNoopForMachoTarget(MCInst &NopInst) const {
+ NopInst.setOpcode(X86::NOOP);
+}
+
diff --git a/lib/Target/X86/X86InstrInfo.h b/lib/Target/X86/X86InstrInfo.h
index 3626f96..52a9050 100644
--- a/lib/Target/X86/X86InstrInfo.h
+++ b/lib/Target/X86/X86InstrInfo.h
@@ -693,6 +693,8 @@
int64_t Offset1, int64_t Offset2,
unsigned NumLoads) const;
+ virtual void getNoopForMachoTarget(MCInst &NopInst) const;
+
virtual
bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const;