[WebAssembly] Add pattern for relaxed nmadd

llvm/include/llvm/Target/TargetSelectionDAG.td

@@ -1147,6 +1147,9 @@ def fadd_contract : PatFrag<(ops node:$a, node:$b), (fadd node:$a, node:$b),[{
   return N->getFlags().hasAllowContract();
 }]>;
 
+def fsub_contract : PatFrag<(ops node:$a, node:$b), (fsub node:$a, node:$b),[{
+  return N->getFlags().hasAllowContract();
+}]>;
 
 def not  : PatFrag<(ops node:$in), (xor node:$in, -1)>;
 def vnot : PatFrag<(ops node:$in), (xor node:$in, immAllOnesV)>;

llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td

@@ -1540,6 +1540,8 @@ multiclass SIMDMADD<Vec vec, bits<32> simdopA, bits<32> simdopS, list<Predicate>
   def : Pat<(fadd_contract (vec.vt V128:$a), (fmul_contract (vec.vt V128:$b), (vec.vt V128:$c))),
              (!cast<Instruction>("MADD_"#vec) V128:$a, V128:$b, V128:$c)>, Requires<[HasRelaxedSIMD]>;
 
+  def : Pat<(fsub_contract (vec.vt V128:$a), (fmul_contract (vec.vt V128:$b), (vec.vt V128:$c))),
+             (!cast<Instruction>("NMADD_"#vec) V128:$a, V128:$b, V128:$c)>, Requires<[HasRelaxedSIMD]>;
 }
 
 defm "" : SIMDMADD<F32x4, 0x105, 0x106, [HasRelaxedSIMD]>;

llvm/test/CodeGen/WebAssembly/simd-relaxed-fnma.ll

@@ -0,0 +1,145 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers  -mattr=+fp16,+simd128,+relaxed-simd | FileCheck %s --check-prefix=RELAXED
+; RUN: llc < %s -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers  -mattr=+fp16,+simd128,              | FileCheck %s --check-prefix=STRICT
+
+target triple = "wasm32"
+
+define double @fsub_fmul_contract_f64(double %a, double %b, double %c) {
+; RELAXED-LABEL: fsub_fmul_contract_f64:
+; RELAXED:         .functype fsub_fmul_contract_f64 (f64, f64, f64) -> (f64)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f64.mul $push0=, $1, $0
+; RELAXED-NEXT:    f64.sub $push1=, $2, $pop0
+; RELAXED-NEXT:    return $pop1
+;
+; STRICT-LABEL: fsub_fmul_contract_f64:
+; STRICT:         .functype fsub_fmul_contract_f64 (f64, f64, f64) -> (f64)
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f64.mul $push0=, $1, $0
+; STRICT-NEXT:    f64.sub $push1=, $2, $pop0
+; STRICT-NEXT:    return $pop1
+  %mul = fmul contract double %b, %a
+  %sub = fsub contract double %c, %mul
+  ret double %sub
+}
+
+define <4 x float> @fsub_fmul_contract_4xf32(<4 x float> %a, <4 x float> %b, <4 x float> %c) {
+; RELAXED-LABEL: fsub_fmul_contract_4xf32:
+; RELAXED:         .functype fsub_fmul_contract_4xf32 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f32x4.relaxed_nmadd $push0=, $2, $1, $0
+; RELAXED-NEXT:    return $pop0
+;
+; STRICT-LABEL: fsub_fmul_contract_4xf32:
+; STRICT:         .functype fsub_fmul_contract_4xf32 (v128, v128, v128) -> (v128)
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f32x4.mul $push0=, $1, $0
+; STRICT-NEXT:    f32x4.sub $push1=, $2, $pop0
+; STRICT-NEXT:    return $pop1
+  %mul = fmul contract <4 x float> %b, %a
+  %sub = fsub contract <4 x float> %c, %mul
+  ret <4 x float> %sub
+}
+
+
+define <8 x half> @fsub_fmul_contract_8xf16(<8 x half> %a, <8 x half> %b, <8 x half> %c) {
+; RELAXED-LABEL: fsub_fmul_contract_8xf16:
+; RELAXED:         .functype fsub_fmul_contract_8xf16 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f16x8.relaxed_nmadd $push0=, $2, $1, $0
+; RELAXED-NEXT:    return $pop0
+;
+; STRICT-LABEL: fsub_fmul_contract_8xf16:
+; STRICT:         .functype fsub_fmul_contract_8xf16 (v128, v128, v128) -> (v128)
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f16x8.mul $push0=, $1, $0
+; STRICT-NEXT:    f16x8.sub $push1=, $2, $pop0
+; STRICT-NEXT:    return $pop1
+  %mul = fmul contract <8 x half> %b, %a
+  %sub = fsub contract <8 x half> %c, %mul
+  ret <8 x half> %sub
+}
+
+
+define <4 x float> @fsub_fmul_4xf32(<4 x float> %a, <4 x float> %b, <4 x float> %c) {
+; RELAXED-LABEL: fsub_fmul_4xf32:
+; RELAXED:         .functype fsub_fmul_4xf32 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f32x4.mul $push0=, $1, $0
+; RELAXED-NEXT:    f32x4.sub $push1=, $2, $pop0
+; RELAXED-NEXT:    return $pop1
+;
+; STRICT-LABEL: fsub_fmul_4xf32:
+; STRICT:         .functype fsub_fmul_4xf32 (v128, v128, v128) -> (v128)
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f32x4.mul $push0=, $1, $0
+; STRICT-NEXT:    f32x4.sub $push1=, $2, $pop0
+; STRICT-NEXT:    return $pop1
+  %mul = fmul <4 x float> %b, %a
+  %sub = fsub contract <4 x float> %c, %mul
+  ret <4 x float> %sub
+}
+
+define <8 x float> @fsub_fmul_contract_8xf32(<8 x float> %a, <8 x float> %b, <8 x float> %c) {
+; RELAXED-LABEL: fsub_fmul_contract_8xf32:
+; RELAXED:         .functype fsub_fmul_contract_8xf32 (i32, v128, v128, v128, v128, v128, v128) -> ()
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f32x4.relaxed_nmadd $push0=, $6, $4, $2
+; RELAXED-NEXT:    v128.store 16($0), $pop0
+; RELAXED-NEXT:    f32x4.relaxed_nmadd $push1=, $5, $3, $1
+; RELAXED-NEXT:    v128.store 0($0), $pop1
+; RELAXED-NEXT:    return
+;
+; STRICT-LABEL: fsub_fmul_contract_8xf32:
+; STRICT:         .functype fsub_fmul_contract_8xf32 (i32, v128, v128, v128, v128, v128, v128) -> ()
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f32x4.mul $push0=, $4, $2
+; STRICT-NEXT:    f32x4.sub $push1=, $6, $pop0
+; STRICT-NEXT:    v128.store 16($0), $pop1
+; STRICT-NEXT:    f32x4.mul $push2=, $3, $1
+; STRICT-NEXT:    f32x4.sub $push3=, $5, $pop2
+; STRICT-NEXT:    v128.store 0($0), $pop3
+; STRICT-NEXT:    return
+  %mul = fmul contract <8 x float> %b, %a
+  %sub = fsub contract <8 x float> %c, %mul
+  ret <8 x float> %sub
+}
+
+
+define <2 x double> @fsub_fmul_contract_2xf64(<2 x double> %a, <2 x double> %b, <2 x double> %c) {
+; RELAXED-LABEL: fsub_fmul_contract_2xf64:
+; RELAXED:         .functype fsub_fmul_contract_2xf64 (v128, v128, v128) -> (v128)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f64x2.relaxed_nmadd $push0=, $2, $1, $0
+; RELAXED-NEXT:    return $pop0
+;
+; STRICT-LABEL: fsub_fmul_contract_2xf64:
+; STRICT:         .functype fsub_fmul_contract_2xf64 (v128, v128, v128) -> (v128)
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f64x2.mul $push0=, $1, $0
+; STRICT-NEXT:    f64x2.sub $push1=, $2, $pop0
+; STRICT-NEXT:    return $pop1
+  %mul = fmul contract <2 x double> %b, %a
+  %sub = fsub contract <2 x double> %c, %mul
+  ret <2 x double> %sub
+}
+
+define float @fsub_fmul_contract_f32(float %a, float %b, float %c) {
+; RELAXED-LABEL: fsub_fmul_contract_f32:
+; RELAXED:         .functype fsub_fmul_contract_f32 (f32, f32, f32) -> (f32)
+; RELAXED-NEXT:  # %bb.0:
+; RELAXED-NEXT:    f32.mul $push0=, $1, $0
+; RELAXED-NEXT:    f32.sub $push1=, $2, $pop0
+; RELAXED-NEXT:    return $pop1
+;
+; STRICT-LABEL: fsub_fmul_contract_f32:
+; STRICT:         .functype fsub_fmul_contract_f32 (f32, f32, f32) -> (f32)
+; STRICT-NEXT:  # %bb.0:
+; STRICT-NEXT:    f32.mul $push0=, $1, $0
+; STRICT-NEXT:    f32.sub $push1=, $2, $pop0
+; STRICT-NEXT:    return $pop1
+  %mul = fmul contract float %b, %a
+  %sub = fsub contract float %c, %mul
+  ret float %sub
+}
+