Don't form PPC CTR loops for over-sized exit counts
Although you can't generate this from C on PPC64, if you have a loop using a
64-bit counter on PPC32 then you can't form a CTR-based loop for it. This had
been cauing the PPCCTRLoops pass to assert.
Thanks to Joerg Sonnenberger for providing a test case!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185361 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCCTRLoops.cpp b/lib/Target/PowerPC/PPCCTRLoops.cpp
index 08247c2..bfc9495 100644
--- a/lib/Target/PowerPC/PPCCTRLoops.cpp
+++ b/lib/Target/PowerPC/PPCCTRLoops.cpp
@@ -415,6 +415,9 @@
} else if (!SE->isLoopInvariant(EC, L))
continue;
+ if (SE->getTypeSizeInBits(EC->getType()) > (TT.isArch64Bit() ? 64 : 32))
+ continue;
+
// We now have a loop-invariant count of loop iterations (which is not the
// constant zero) for which we know that this loop will not exit via this
// exisiting block.