From ed2ea3e46b753e4a6ea141e48427c50aaeecca55 Mon Sep 17 00:00:00 2001 From: Sam Parker Date: Tue, 30 Jul 2019 08:08:44 +0000 Subject: [ARM][LowOverheadLoops] Revert non-header LE target Revert the hardware loop upon finding a LoopEnd that doesn't target the loop header, instead of asserting a failure. Differential Revision: https://reviews.llvm.org/D65268 llvm-svn: 367296 --- llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp') diff --git a/llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp b/llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp index dd36702aa48..303986a0b49 100644 --- a/llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp +++ b/llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp @@ -207,9 +207,15 @@ bool ARMLowOverheadLoops::ProcessLoop(MachineLoop *ML) { return false; } - if (!End->getOperand(1).isMBB() || - End->getOperand(1).getMBB() != ML->getHeader()) - report_fatal_error("Expected LoopEnd to target Loop Header"); + if (!End->getOperand(1).isMBB()) + report_fatal_error("Expected LoopEnd to target basic block"); + + // TODO Maybe there's cases where the target doesn't have to be the header, + // but for now be safe and revert. + if (End->getOperand(1).getMBB() != ML->getHeader()) { + LLVM_DEBUG(dbgs() << "ARM Loops: LoopEnd is not targetting header.\n"); + Revert = true; + } // The WLS and LE instructions have 12-bits for the label offset. WLS // requires a positive offset, while LE uses negative. -- cgit v1.2.3