From ddae4bd68358df7415d532e6930c0ba9c60f6cb5 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 8 Jan 2007 23:04:05 +0000 Subject: [PATCH] Implement some trivial FP foldings when -enable-unsafe-fp-math is specified. This implements CodeGen/PowerPC/unsafe-math.ll git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33024 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 33509536eb5..76a60f0f478 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -35,6 +35,7 @@ #include "llvm/Support/Debug.h" #include "llvm/Support/MathExtras.h" #include "llvm/Target/TargetLowering.h" +#include "llvm/Target/TargetOptions.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/CommandLine.h" #include @@ -2401,6 +2402,13 @@ SDOperand DAGCombiner::visitFADD(SDNode *N) { // fold ((-A) + B) -> B-A if (N0.getOpcode() == ISD::FNEG) return DAG.getNode(ISD::FSUB, VT, N1, N0.getOperand(0)); + + // If allowed, fold (fadd (fadd x, c1), c2) -> (fadd x, (fadd c1, c2)) + if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FADD && + N0.Val->hasOneUse() && isa(N0.getOperand(1))) + return DAG.getNode(ISD::FADD, VT, N0.getOperand(0), + DAG.getNode(ISD::FADD, VT, N0.getOperand(1), N1)); + return SDOperand(); } @@ -2436,6 +2444,13 @@ SDOperand DAGCombiner::visitFMUL(SDNode *N) { // fold (fmul X, 2.0) -> (fadd X, X) if (N1CFP && N1CFP->isExactlyValue(+2.0)) return DAG.getNode(ISD::FADD, VT, N0, N0); + + // If allowed, fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2)) + if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FMUL && + N0.Val->hasOneUse() && isa(N0.getOperand(1))) + return DAG.getNode(ISD::FMUL, VT, N0.getOperand(0), + DAG.getNode(ISD::FMUL, VT, N0.getOperand(1), N1)); + return SDOperand(); } -- 2.34.1