From 57da25231aaa5f9bbc981cd8bb8722ff129bf8a0 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Tue, 23 Aug 2005 20:22:50 +0000
Subject: [PATCH] Fix PR618 and Regression/CodeGen/CBackend/2005-08-23-Fmod.ll
 by not emitting x%y for 'rem' on fp values.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22984 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/CBackend/CBackend.cpp | 14 ++++++++++++++
 lib/Target/CBackend/Writer.cpp   | 14 ++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index fc87afd2062..df06c7ca24d 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -871,6 +871,9 @@ bool CWriter::doInitialization(Module &M) {
   }
 
   // Function declarations
+  Out << "double fmod(double, double);\n";   // Support for FP rem
+  Out << "float fmodf(float, float);\n";
+  
   if (!M.empty()) {
     Out << "\n/* Function Declarations */\n";
     for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
@@ -1349,6 +1352,17 @@ void CWriter::visitBinaryOperator(Instruction &I) {
     Out << "-(";
     writeOperand(BinaryOperator::getNegArgument(cast<BinaryOperator>(&I)));
     Out << ")";
+  } else if (I.getOpcode() == Instruction::Rem && 
+             I.getType()->isFloatingPoint()) {
+    // Output a call to fmod/fmodf instead of emitting a%b
+    if (I.getType() == Type::FloatTy)
+      Out << "fmodf(";
+    else
+      Out << "fmod(";
+    writeOperand(I.getOperand(0));
+    Out << ", ";
+    writeOperand(I.getOperand(1));
+    Out << ")";
   } else {
     writeOperand(I.getOperand(0));
 
diff --git a/lib/Target/CBackend/Writer.cpp b/lib/Target/CBackend/Writer.cpp
index fc87afd2062..df06c7ca24d 100644
--- a/lib/Target/CBackend/Writer.cpp
+++ b/lib/Target/CBackend/Writer.cpp
@@ -871,6 +871,9 @@ bool CWriter::doInitialization(Module &M) {
   }
 
   // Function declarations
+  Out << "double fmod(double, double);\n";   // Support for FP rem
+  Out << "float fmodf(float, float);\n";
+  
   if (!M.empty()) {
     Out << "\n/* Function Declarations */\n";
     for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
@@ -1349,6 +1352,17 @@ void CWriter::visitBinaryOperator(Instruction &I) {
     Out << "-(";
     writeOperand(BinaryOperator::getNegArgument(cast<BinaryOperator>(&I)));
     Out << ")";
+  } else if (I.getOpcode() == Instruction::Rem && 
+             I.getType()->isFloatingPoint()) {
+    // Output a call to fmod/fmodf instead of emitting a%b
+    if (I.getType() == Type::FloatTy)
+      Out << "fmodf(";
+    else
+      Out << "fmod(";
+    writeOperand(I.getOperand(0));
+    Out << ", ";
+    writeOperand(I.getOperand(1));
+    Out << ")";
   } else {
     writeOperand(I.getOperand(0));