The concept of strict floating point nodes was added into LLVM in https://reviews.llvm.org/D55506.
This is the first patch to add constraint fp support about exception part for PowerPC targetD55506 introduced concept of strict-fp nodes into LLVM. This patch is to add strict-fp exception support to PowerPC backend, and only contains basic arithmetic operations (`+`, `-`, `*`, which only handles basic +-*/ operations.
Remaining`/`). Patch for the rest of floating point operation works will be submittedbe in follow-uping patches.