From 0fad5c480e79d476651d50262573e019aac5f5c5 Mon Sep 17 00:00:00 2001
From: Michael Ilseman <milseman@apple.com>
Date: Tue, 27 Nov 2012 00:43:38 +0000
Subject: [PATCH] Fast-math flags for the bitcode

Added in bitcode enum for the serializing of fast-math flags. Added in the reading/writing of fast-math flags from the OptimizationFlags record for BinaryOps.

llvm-svn: 168646
---
 include/llvm/Bitcode/LLVMBitCodes.h  | 10 ++++++++++
 lib/Bitcode/Reader/BitcodeReader.cpp | 15 +++++++++++++++
 lib/Bitcode/Writer/BitcodeWriter.cpp | 12 ++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/include/llvm/Bitcode/LLVMBitCodes.h b/include/llvm/Bitcode/LLVMBitCodes.h
index 511e3a377a1..3c7c2b3a06f 100644
--- a/include/llvm/Bitcode/LLVMBitCodes.h
+++ b/include/llvm/Bitcode/LLVMBitCodes.h
@@ -240,6 +240,16 @@ namespace bitc {
     PEO_EXACT = 0
   };
 
+  /// Flags for serializing FPMathOperator's
+  /// SubclassOptionalData contents.
+  enum FastMathFlags {
+    FMF_UNSAFE_ALGEBRA   = 0,
+    FMF_NO_NANS          = 1,
+    FMF_NO_INFS          = 2,
+    FMF_NO_SIGNED_ZEROS  = 3,
+    FMF_ALLOW_RECIPROCAL = 4
+  };
+
   /// Encoded AtomicOrdering values.
   enum AtomicOrderingCodes {
     ORDERING_NOTATOMIC = 0,
diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index d3c8678578d..f31637e044f 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -2044,7 +2044,22 @@ bool BitcodeReader::ParseFunctionBody(Function *F) {
                    Opc == Instruction::AShr) {
           if (Record[OpNum] & (1 << bitc::PEO_EXACT))
             cast<BinaryOperator>(I)->setIsExact(true);
+        } else if (isa<FPMathOperator>(I)) {
+          FastMathFlags FMF;
+          FMF.UnsafeAlgebra =
+            0 != (Record[OpNum] & (1 << bitc::FMF_UNSAFE_ALGEBRA));
+          FMF.NoNaNs
+            = 0 != (Record[OpNum] & (1 << bitc::FMF_NO_NANS));
+          FMF.NoInfs
+            = 0 != (Record[OpNum] & (1 << bitc::FMF_NO_INFS));
+          FMF.NoSignedZeros
+            = 0 != (Record[OpNum] & (1 << bitc::FMF_NO_SIGNED_ZEROS));
+          FMF.AllowReciprocal
+            = 0 != (Record[OpNum] & (1 << bitc::FMF_ALLOW_RECIPROCAL));
+          if (FMF.any())
+            I->setFastMathFlags(FMF);
         }
+
       }
       break;
     }
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index cf3c9fd74eb..6206479b8d7 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -553,6 +553,18 @@ static uint64_t GetOptimizationFlags(const Value *V) {
                dyn_cast<PossiblyExactOperator>(V)) {
     if (PEO->isExact())
       Flags |= 1 << bitc::PEO_EXACT;
+  } else if (const FPMathOperator *FPMO =
+             dyn_cast<const FPMathOperator>(V)) {
+    if (FPMO->hasUnsafeAlgebra())
+      Flags |= 1 << bitc::FMF_UNSAFE_ALGEBRA;
+    if (FPMO->hasNoNaNs())
+      Flags |= 1 << bitc::FMF_NO_NANS;
+    if (FPMO->hasNoInfs())
+      Flags |= 1 << bitc::FMF_NO_INFS;
+    if (FPMO->hasNoSignedZeros())
+      Flags |= 1 << bitc::FMF_NO_SIGNED_ZEROS;
+    if (FPMO->hasAllowReciprocal())
+      Flags |= 1 << bitc::FMF_ALLOW_RECIPROCAL;
   }
 
   return Flags;