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

1 files changed, 16 insertions, 0 deletions

diff --git a/lib/AsmParser/LLParser.h b/lib/AsmParser/LLParser.h
index 9f9672d67b..8e04705a7b 100644
--- a/lib/AsmParser/LLParser.h
+++ b/lib/AsmParser/LLParser.h
@@ -18,6 +18,7 @@
 #include "llvm/Attributes.h"
 #include "llvm/Instructions.h"
 #include "llvm/Module.h"
+#include "llvm/Operator.h"
 #include "llvm/Type.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringMap.h"
@@ -154,6 +155,21 @@ namespace llvm {
       Lex.Lex();
       return true;
     }
+
+    FastMathFlags EatFastMathFlagsIfPresent() {
+      FastMathFlags FMF;
+      while (true)
+        switch (Lex.getKind()) {
+        case lltok::kw_fast: FMF.UnsafeAlgebra   = true; Lex.Lex(); continue;
+        case lltok::kw_nnan: FMF.NoNaNs          = true; Lex.Lex(); continue;
+        case lltok::kw_ninf: FMF.NoInfs          = true; Lex.Lex(); continue;
+        case lltok::kw_nsz:  FMF.NoSignedZeros   = true; Lex.Lex(); continue;
+        case lltok::kw_arcp: FMF.AllowReciprocal = true; Lex.Lex(); continue;
+        default: return FMF;
+        }
+      return FMF;
+    }
+
     bool ParseOptionalToken(lltok::Kind T, bool &Present, LocTy *Loc = 0) {
       if (Lex.getKind() != T) {
         Present = false;