Fast-math flags for LLVM IR parsing and printing

Added in the ability to read LLVM IR text that contains fast-math flags as a sequence of capital letters separated by spaces in any order. Added in the printing of the fast-math flags in a canonical order, and don't print the other flags when 'fast' is specified, as 'fast' implies all the others.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168645 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 41cca68..65f4245 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -3012,7 +3012,17 @@
   }
   case lltok::kw_fadd:
   case lltok::kw_fsub:
-  case lltok::kw_fmul:    return ParseArithmetic(Inst, PFS, KeywordVal, 2);
+  case lltok::kw_fmul:
+  case lltok::kw_fdiv:
+  case lltok::kw_frem: {
+    FastMathFlags FMF = EatFastMathFlagsIfPresent();
+    int Res = ParseArithmetic(Inst, PFS, KeywordVal, 2);
+    if (Res != 0)
+      return Res;
+    if (FMF.any())
+      Inst->setFastMathFlags(FMF);
+    return 0;
+  }
 
   case lltok::kw_sdiv:
   case lltok::kw_udiv:
@@ -3027,8 +3037,6 @@
 
   case lltok::kw_urem:
   case lltok::kw_srem:   return ParseArithmetic(Inst, PFS, KeywordVal, 1);
-  case lltok::kw_fdiv:
-  case lltok::kw_frem:   return ParseArithmetic(Inst, PFS, KeywordVal, 2);
   case lltok::kw_and:
   case lltok::kw_or:
   case lltok::kw_xor:    return ParseLogical(Inst, PFS, KeywordVal);