// FMA3 - Intel 3 operand Fused Multiply-Add instructions
//===----------------------------------------------------------------------===//
-let Constraints = "$src1 = $dst" in {
+// For all FMA opcodes declared in fma3p_rm and fma3s_rm milticlasses defined
+// below, both the register and memory variants are commutable.
+// For the register form the commutable operands are 1, 2 and 3.
+// For the memory variant the folded operand must be in 3. Thus,
+// in that case, only the operands 1 and 2 can be swapped.
+// Commuting some of operands may require the opcode change.
+// FMA*213*:
+// operands 1 and 2 (memory & register forms): *213* --> *213*(no changes);
+// operands 1 and 3 (register forms only): *213* --> *231*;
+// operands 2 and 3 (register forms only): *213* --> *132*.
+// FMA*132*:
+// operands 1 and 2 (memory & register forms): *132* --> *231*;
+// operands 1 and 3 (register forms only): *132* --> *132*(no changes);
+// operands 2 and 3 (register forms only): *132* --> *213*.
+// FMA*231*:
+// operands 1 and 2 (memory & register forms): *231* --> *132*;
+// operands 1 and 3 (register forms only): *231* --> *213*;
+// operands 2 and 3 (register forms only): *231* --> *231*(no changes).
+
+let Constraints = "$src1 = $dst", hasSideEffects = 0, isCommutable = 1 in
multiclass fma3p_rm<bits<8> opc, string OpcodeStr,
PatFrag MemFrag128, PatFrag MemFrag256,
ValueType OpVT128, ValueType OpVT256,
(OpVT256 (Op VR256:$src2, VR256:$src1,
(MemFrag256 addr:$src3))))]>, VEX_L;
}
-} // Constraints = "$src1 = $dst"
multiclass fma3p_forms<bits<8> opc132, bits<8> opc213, bits<8> opc231,
string OpcodeStr, string PackTy,
PatFrag MemFrag128, PatFrag MemFrag256,
SDNode Op, ValueType OpTy128, ValueType OpTy256> {
- let isCommutable = 1 in
defm r213 : fma3p_rm<opc213,
!strconcat(OpcodeStr, "213", PackTy),
MemFrag128, MemFrag256, OpTy128, OpTy256, Op>;
-let neverHasSideEffects = 1 in {
defm r132 : fma3p_rm<opc132,
!strconcat(OpcodeStr, "132", PackTy),
MemFrag128, MemFrag256, OpTy128, OpTy256>;
defm r231 : fma3p_rm<opc231,
!strconcat(OpcodeStr, "231", PackTy),
MemFrag128, MemFrag256, OpTy128, OpTy256>;
-} // neverHasSideEffects = 1
}
// Fused Multiply-Add
v4f64>, VEX_W;
}
-let Constraints = "$src1 = $dst" in {
-multiclass fma3s_rm<bits<8> opc, string OpcodeStr, X86MemOperand x86memop,
- RegisterClass RC, ValueType OpVT, PatFrag mem_frag,
+// All source register operands of FMA opcodes defined in fma3s_rm multiclass
+// can be commuted. In many cases such commute transformation requres an opcode
+// adjustment, for example, commuting the operands 1 and 2 in FMA*132 form
+// would require an opcode change to FMA*231:
+// FMA*132* reg1, reg2, reg3; // reg1 * reg3 + reg2;
+// -->
+// FMA*231* reg2, reg1, reg3; // reg1 * reg3 + reg2;
+// Please see more detailed comment at the very beginning of the section
+// defining FMA3 opcodes above.
+let Constraints = "$src1 = $dst", isCommutable = 1, hasSideEffects = 0 in
+multiclass fma3s_rm<bits<8> opc, string OpcodeStr,
+ X86MemOperand x86memop, RegisterClass RC,
SDPatternOperator OpNode = null_frag> {
let usesCustomInserter = 1 in
def r : FMA3<opc, MRMSrcReg, (outs RC:$dst),
(ins RC:$src1, RC:$src2, RC:$src3),
!strconcat(OpcodeStr,
"\t{$src3, $src2, $dst|$dst, $src2, $src3}"),
- [(set RC:$dst,
- (OpVT (OpNode RC:$src2, RC:$src1, RC:$src3)))]>;
+ [(set RC:$dst, (OpNode RC:$src2, RC:$src1, RC:$src3))]>;
let mayLoad = 1 in
def m : FMA3<opc, MRMSrcMem, (outs RC:$dst),
!strconcat(OpcodeStr,
"\t{$src3, $src2, $dst|$dst, $src2, $src3}"),
[(set RC:$dst,
- (OpVT (OpNode RC:$src2, RC:$src1,
- (mem_frag addr:$src3))))]>;
+ (OpNode RC:$src2, RC:$src1, (load addr:$src3)))]>;
+}
+
+// These FMA*_Int instructions are defined specially for being used when
+// the scalar FMA intrinsics are lowered to machine instructions, and in that
+// sence they are similar to existing ADD*_Int, SUB*_Int, MUL*_Int, etc.
+// instructions.
+//
+// FIXME: The FMA*_Int instructions are TEMPORARILY defined as NOT commutable.
+// Commuting the 2nd and 3rd source register operands of FMAs is quite trivial
+// and the corresponding optimization has been developed (please see
+// http://reviews.llvm.org/D13269 for details). The optimization though needs
+// some minor tuning to enable it for FMA*_Int opcodes.
+// Commuting the 1st operand of FMA*_Int requires some additional analysis,
+// the commute optimization is legal only if all users of FMA*_Int use only
+// the lowest element of the FMA*_Int instruction.
+let Constraints = "$src1 = $dst", isCommutable = 0, isCodeGenOnly =1,
+ hasSideEffects = 0 in
+multiclass fma3s_rm_int<bits<8> opc, string OpcodeStr,
+ Operand memopr, RegisterClass RC> {
+ def r_Int : FMA3<opc, MRMSrcReg, (outs RC:$dst),
+ (ins RC:$src1, RC:$src2, RC:$src3),
+ !strconcat(OpcodeStr,
+ "\t{$src3, $src2, $dst|$dst, $src2, $src3}"),
+ []>;
+
+ let mayLoad = 1 in
+ def m_Int : FMA3<opc, MRMSrcMem, (outs RC:$dst),
+ (ins RC:$src1, RC:$src2, memopr:$src3),
+ !strconcat(OpcodeStr,
+ "\t{$src3, $src2, $dst|$dst, $src2, $src3}"),
+ []>;
}
-} // Constraints = "$src1 = $dst"
multiclass fma3s_forms<bits<8> opc132, bits<8> opc213, bits<8> opc231,
- string OpStr, string PackTy, string PT2, Intrinsic Int,
- SDNode OpNode, RegisterClass RC, ValueType OpVT,
- X86MemOperand x86memop, Operand memop, PatFrag mem_frag,
- ComplexPattern mem_cpat> {
-let neverHasSideEffects = 1 in {
- defm r132 : fma3s_rm<opc132, !strconcat(OpStr, "132", PackTy),
- x86memop, RC, OpVT, mem_frag>;
- defm r231 : fma3s_rm<opc231, !strconcat(OpStr, "231", PackTy),
- x86memop, RC, OpVT, mem_frag>;
+ string OpStr, string PackTy,
+ SDNode OpNode, RegisterClass RC,
+ X86MemOperand x86memop> {
+ defm r132 : fma3s_rm<opc132, !strconcat(OpStr, "132", PackTy), x86memop, RC>;
+ defm r213 : fma3s_rm<opc213, !strconcat(OpStr, "213", PackTy), x86memop, RC,
+ OpNode>;
+ defm r231 : fma3s_rm<opc231, !strconcat(OpStr, "231", PackTy), x86memop, RC>;
}
-let isCommutable = 1 in
-defm r213 : fma3s_rm<opc213, !strconcat(OpStr, "213", PackTy),
- x86memop, RC, OpVT, mem_frag, OpNode>;
+// The FMA 213 form is created for lowering of scalar FMA intrinscis
+// to machine instructions.
+// The FMA 132 form can trivially be get by commuting the 2nd and 3rd operands
+// of FMA 213 form.
+// The FMA 231 form can be get only by commuting the 1st operand of 213 or 132
+// forms and is possible only after special analysis of all uses of the initial
+// instruction. Such analysis do not exist yet and thus introducing the 231
+// form of FMA*_Int instructions is done using an optimistic assumption that
+// such analysis will be implemented eventually.
+multiclass fma3s_int_forms<bits<8> opc132, bits<8> opc213, bits<8> opc231,
+ string OpStr, string PackTy,
+ RegisterClass RC, Operand memop> {
+ defm r132 : fma3s_rm_int<opc132, !strconcat(OpStr, "132", PackTy),
+ memop, RC>;
+ defm r213 : fma3s_rm_int<opc213, !strconcat(OpStr, "213", PackTy),
+ memop, RC>;
+ defm r231 : fma3s_rm_int<opc231, !strconcat(OpStr, "231", PackTy),
+ memop, RC>;
}
multiclass fma3s<bits<8> opc132, bits<8> opc213, bits<8> opc231,
string OpStr, Intrinsic IntF32, Intrinsic IntF64,
SDNode OpNode> {
- defm SS : fma3s_forms<opc132, opc213, opc231, OpStr, "ss", "SS", IntF32, OpNode,
- FR32, f32, f32mem, ssmem, loadf32, sse_load_f32>;
- defm SD : fma3s_forms<opc132, opc213, opc231, OpStr, "sd", "PD", IntF64, OpNode,
- FR64, f64, f64mem, sdmem, loadf64, sse_load_f64>, VEX_W;
+ defm SS : fma3s_forms<opc132, opc213, opc231, OpStr, "ss", OpNode,
+ FR32, f32mem>,
+ fma3s_int_forms<opc132, opc213, opc231, OpStr, "ss", VR128, ssmem>;
+ defm SD : fma3s_forms<opc132, opc213, opc231, OpStr, "sd", OpNode,
+ FR64, f64mem>,
+ fma3s_int_forms<opc132, opc213, opc231, OpStr, "sd", VR128, sdmem>,
+ VEX_W;
+ // These patterns use the 123 ordering, instead of 213, even though
+ // they match the intrinsic to the 213 version of the instruction.
+ // This is because src1 is tied to dest, and the scalar intrinsics
+ // require the pass-through values to come from the first source
+ // operand, not the second.
def : Pat<(IntF32 VR128:$src1, VR128:$src2, VR128:$src3),
(COPY_TO_REGCLASS
- (!cast<Instruction>(NAME#"SSr213r")
- (COPY_TO_REGCLASS $src2, FR32),
+ (!cast<Instruction>(NAME#"SSr213r_Int")
(COPY_TO_REGCLASS $src1, FR32),
+ (COPY_TO_REGCLASS $src2, FR32),
(COPY_TO_REGCLASS $src3, FR32)),
VR128)>;
def : Pat<(IntF64 VR128:$src1, VR128:$src2, VR128:$src3),
(COPY_TO_REGCLASS
- (!cast<Instruction>(NAME#"SDr213r")
- (COPY_TO_REGCLASS $src2, FR64),
+ (!cast<Instruction>(NAME#"SDr213r_Int")
(COPY_TO_REGCLASS $src1, FR64),
+ (COPY_TO_REGCLASS $src2, FR64),
(COPY_TO_REGCLASS $src3, FR64)),
VR128)>;
}