Generate the fchs instruction to negate a floating point number
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11078 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 6cd514b..1dc63bb 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -388,6 +388,10 @@
class FPInst<string n, bits<8> o, Format F, ArgType t, FPFormat fp>
: X86Inst<n, o, F, t> { let FPForm = fp; let FPFormBits = FPForm.Value; }
+// Pseudo instructions for floating point. We use these pseudo instructions
+// because they can be expanded by the fp spackifier into one of many different
+// forms of instructions for doing these operations. Until the stackifier runs,
+// we prefer to be abstract.
def FpMOV : FPInst<"FMOV", 0, Pseudo, ArgF80, SpecialFP>; // f1 = fmov f2
def FpADD : FPInst<"FADD", 0, Pseudo, ArgF80, TwoArgFP>; // f1 = fadd f2, f3
def FpSUB : FPInst<"FSUB", 0, Pseudo, ArgF80, TwoArgFP>; // f1 = fsub f2, f3
@@ -429,6 +433,10 @@
def FLD0 : FPInst<"fldz", 0xEE, RawFrm, ArgF80, ZeroArgFP>, D9;
def FLD1 : FPInst<"fld1", 0xE8, RawFrm, ArgF80, ZeroArgFP>, D9;
+
+// Unary read-modify-write operations...
+def FCHS : FPInst<"fchs", 0xE0, RawFrm, ArgF80, OneArgFPRW>, D9, Imp<[ST0],[ST0]>; // f1 = fchs f2
+
// Binary arithmetic operations...
class FPST0rInst<string n, bits<8> o>
: X86Inst<n, o, AddRegFrm, ArgF80>, D8 {