Tag build swift-DEVELOPMENT-SNAPSHOT-2016-08-30-a
[SystemZ] Disable shrinking of SNaN constants (#20)
When expanding FP constants, we attempt to shrink doubles to floats and perform an extending load.
However, on SystemZ, and possibly on other targets (I've only confirmed the problem on SystemZ), the FP extending load instruction may convert SNaN into QNaN, or may cause an exception. So in the general case, we would still like to shrink FP constants, but SNaNs should be left as doubles.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277602 91177308-0d34-0410-b5e6-96231b3b80d8
LLLexer.cpp: Avoid using BitsToDouble() to preserve SNaN like "double 0x7FF4000000000000".
We should not use double (or float) in the LLVM, unless it is really needed. x87 FP register doesn't preserve SNaN to move the value.
FIXME: APFloat() may have the constructor by raw bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277813 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed
