[PATCH] D81869: Modify FPFeatures to use delta not absolute settings to solve PCH compatibility problems

[Melanie Blower via Phabricator via llvm-commits]

mibintc marked an inline comment as done.
mibintc added a comment.

@rjmccall You suggested that the FPFeatures could be delta instead of absolute settings, I think this is approximately what you mean.  This is a rough patch employing that idea, would welcome your early comments.  There are 2 clang tests that are failing with this patch, I need to dig into those.

Failed Tests (2):

  Clang :: CodeGen/fp-floatcontrol-stack.cpp
  Clang :: PCH/pragma-floatcontrol.c



================
Comment at: llvm/include/llvm/ADT/FloatingPointMode.h:43
   // Special values.
+  Unset = 6,      ///< Denotes an unset value, (for clang, must fit in 3 bits)
   Dynamic = 7,    ///< Denotes mode unknown at compile time.
----------------
I added "unset" enumerals to the 3 enumeration values. Note that I can't just use the "invalid" enumeration since the clang field is only 3 bits wide so Invalid would appear to equal Dynamic


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D81869/new/

https://reviews.llvm.org/D81869