diff options
Diffstat (limited to 'llvm/lib/CodeGen')
| -rw-r--r-- | llvm/lib/CodeGen/VirtRegRewriter.cpp | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/VirtRegRewriter.cpp b/llvm/lib/CodeGen/VirtRegRewriter.cpp index 361d35e8a89..6370d8fa5cb 100644 --- a/llvm/lib/CodeGen/VirtRegRewriter.cpp +++ b/llvm/lib/CodeGen/VirtRegRewriter.cpp @@ -2033,6 +2033,21 @@ LocalRewriter::RewriteMBB(LiveIntervals *LIs, CanReuse = !ReusedOperands.isClobbered(PhysReg) && Spills.canClobberPhysReg(PhysReg); } + // If this is an asm, and PhysReg is used elsewhere as an earlyclobber + // operand, we can't also use it as an input. (Outputs always come + // before inputs, so we can stop looking at i.) + if (MI.getOpcode()==TargetOpcode::INLINEASM) { + for (unsigned k=0; k<i; ++k) { + MachineOperand &MOk = MI.getOperand(k); + if (!MOk.isReg() || MOk.getReg()==0) + continue; + unsigned VirtRegk = MOk.getReg(); + if (VirtRegk == PhysReg && MOk.isEarlyClobber()) { + CanReuse = false; + break; + } + } + } if (CanReuse) { // If this stack slot value is already available, reuse it! @@ -2103,6 +2118,8 @@ LocalRewriter::RewriteMBB(LiveIntervals *LIs, // To avoid this problem, and to avoid doing a load right after a store, // we emit a copy from PhysReg into the designated register for this // operand. + // + // This case also applies to an earlyclobber'd PhysReg. unsigned DesignatedReg = VRM->getPhys(VirtReg); assert(DesignatedReg && "Must map virtreg to physreg!"); |
