From 0b984995b736f022eb429cf6c475315778c4acc8 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Thu, 23 Aug 2007 23:46:33 +0000
Subject: [PATCH] implement complex subtraction

llvm-svn: 41345
---
 clang/CodeGen/CGComplexExpr.cpp | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/clang/CodeGen/CGComplexExpr.cpp b/clang/CodeGen/CGComplexExpr.cpp
index 1597f8e2c78b..38cdd05ec9cd 100644
--- a/clang/CodeGen/CGComplexExpr.cpp
+++ b/clang/CodeGen/CGComplexExpr.cpp
@@ -106,7 +106,8 @@ public:
   
   ComplexPairTy VisitBinMul        (const BinaryOperator *E);
   ComplexPairTy VisitBinAdd        (const BinaryOperator *E);
-  // FIXME: sub/div/rem
+  ComplexPairTy VisitBinSub        (const BinaryOperator *E);
+  // FIXME: div/rem
   // GCC rejects and/or/xor for integer complex.
   // Logical and/or always return int, never complex.
 
@@ -225,6 +226,17 @@ ComplexPairTy ComplexExprEmitter::VisitBinAdd(const BinaryOperator *E) {
   return ComplexPairTy(ResR, ResI);
 }
 
+ComplexPairTy ComplexExprEmitter::VisitBinSub(const BinaryOperator *E) {
+  ComplexPairTy LHS = Visit(E->getLHS());
+  ComplexPairTy RHS = Visit(E->getRHS());
+  
+  llvm::Value *ResR = Builder.CreateSub(LHS.first,  RHS.first,  "sub.r");
+  llvm::Value *ResI = Builder.CreateSub(LHS.second, RHS.second, "sub.i");
+  
+  return ComplexPairTy(ResR, ResI);
+}
+
+
 ComplexPairTy ComplexExprEmitter::VisitBinMul(const BinaryOperator *E) {
   ComplexPairTy LHS = Visit(E->getLHS());
   ComplexPairTy RHS = Visit(E->getRHS());