From f2d552eca65253bd8fc5934e4019921bc32b2364 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Tue, 16 Nov 2004 04:30:51 +0000 Subject: [PATCH] Implement a simple FIXME: if we are emitting a basic block address that has already been emitted, we don't have to remember it and deal with it later, just emit it directly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17868 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86CodeEmitter.cpp | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp index c7477448dd2..853e6c12cdf 100644 --- a/lib/Target/X86/X86CodeEmitter.cpp +++ b/lib/Target/X86/X86CodeEmitter.cpp @@ -278,9 +278,19 @@ void Emitter::emitBasicBlock(const MachineBasicBlock &MBB) { /// necessary to resolve this address later (and emits a dummy value). /// void Emitter::emitPCRelativeBlockAddress(const MachineBasicBlock *MBB) { - // FIXME: Emit backward branches directly - BBRefs.push_back(std::make_pair(MBB, MCE.getCurrentPCValue())); - MCE.emitWord(0); + // If this is a backwards branch, we already know the address of the target, + // so just emit the value. + std::map::iterator I = + BasicBlockAddrs.find(MBB); + if (I != BasicBlockAddrs.end()) { + unsigned Location = I->second; + MCE.emitWord(Location-MCE.getCurrentPCValue()-4); + } else { + // Otherwise, remember where this reference was and where it is to so we can + // deal with it later. + BBRefs.push_back(std::make_pair(MBB, MCE.getCurrentPCValue())); + MCE.emitWord(0); + } } /// emitPCRelativeValue - Emit a 32-bit PC relative address.