match a reassociated form of fnmul. This implements CodeGen/ARM/fnmul.ll

llvm-svn: 36660

2 files changed, 9 insertions, 2 deletions

diff --git a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 8108ee4993b..79d58692e9f 100644
--- a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -27,6 +27,7 @@
 #include "llvm/CodeGen/SelectionDAGISel.h"
 #include "llvm/CodeGen/SSARegMap.h"
 #include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetOptions.h"
 #include "llvm/Support/Debug.h"
 using namespace llvm;
 
diff --git a/llvm/lib/Target/ARM/ARMInstrVFP.td b/llvm/lib/Target/ARM/ARMInstrVFP.td
index cac8e4465c9..671e1a48c18 100644
--- a/llvm/lib/Target/ARM/ARMInstrVFP.td
+++ b/llvm/lib/Target/ARM/ARMInstrVFP.td
@@ -139,8 +139,7 @@ def FMULD  : ADI<(ops DPR:$dst, DPR:$a, DPR:$b),
 def FMULS  : ASI<(ops SPR:$dst, SPR:$a, SPR:$b),
                  "fmuls $dst, $a, $b",
                  [(set SPR:$dst, (fmul SPR:$a, SPR:$b))]>;
-
-
+                 
 def FNMULD  : ADI<(ops DPR:$dst, DPR:$a, DPR:$b),
                   "fnmuld $dst, $a, $b",
                   [(set DPR:$dst, (fneg (fmul DPR:$a, DPR:$b)))]>;
@@ -149,6 +148,13 @@ def FNMULS  : ASI<(ops SPR:$dst, SPR:$a, SPR:$b),
                   "fnmuls $dst, $a, $b",
                   [(set SPR:$dst, (fneg (fmul SPR:$a, SPR:$b)))]>;
 
+// Match reassociated forms only if not sign dependent rounding.
+def : Pat<(fmul (fneg DPR:$a), DPR:$b),
+          (FNMULD DPR:$a, DPR:$b)>, Requires<[NoHonorSignDependentRounding]>;
+def : Pat<(fmul (fneg SPR:$a), SPR:$b),
+          (FNMULS SPR:$a, SPR:$b)>, Requires<[NoHonorSignDependentRounding]>;
+
+
 def FSUBD  : ADI<(ops DPR:$dst, DPR:$a, DPR:$b),
                  "fsubd $dst, $a, $b",
                  [(set DPR:$dst, (fsub DPR:$a, DPR:$b))]>;