Make the order creating the ops explicit to make sure the same sequence is

created for different Linux systems.

Author: jsjodin

mlir/lib/Dialect/Math/Transforms/PolynomialApproximation.cpp

@@ -1184,9 +1184,10 @@ ErfcPolynomialApproximation::matchAndRewrite(math::ErfcOp op,
   Value d = builder.create<math::FmaOp>(pos2, a, one);
   r = builder.create<arith::DivFOp>(one, d);
   q = builder.create<math::FmaOp>(p, r, r);
-  e = builder.create<math::FmaOp>(
-      builder.create<math::FmaOp>(q, builder.create<arith::NegFOp>(a), onehalf),
-      pos2, builder.create<arith::SubFOp>(p, q));
+  Value negfa = builder.create<arith::NegFOp>(a);
+  Value fmaqah = builder.create<math::FmaOp>(q, negfa, onehalf);
+  Value psubq = builder.create<arith::SubFOp>(p, q);
+  e = builder.create<math::FmaOp>(fmaqah, pos2, psubq);
   r = builder.create<math::FmaOp>(e, r, q);
 
   Value s = builder.create<arith::MulFOp>(a, a);

mlir/test/Dialect/Math/polynomial-approximation.mlir

@@ -139,10 +139,10 @@ func.func @erf_scalar(%arg0: f32) -> f32 {
 // CHECK-NEXT:         %[[val_20:.*]] = math.fma %[[cst_26]], %[[val_2]], %[[cst_22]] : f32
 // CHECK-NEXT:         %[[val_21:.*]] = arith.divf %[[cst_22]], %[[val_20]] : f32
 // CHECK-NEXT:         %[[val_22:.*]] = math.fma %[[val_19]], %[[val_21]], %[[val_21]] : f32
-// CHECK-NEXT:         %[[val_23:.*]] = arith.subf %[[val_19]], %[[val_22]] : f32
-// CHECK-NEXT:         %[[val_24:.*]] = arith.negf %[[val_2]] : f32
-// CHECK-NEXT:         %[[val_25:.*]] = math.fma %[[val_22]], %[[val_24]], %[[cst_23]] : f32
-// CHECK-NEXT:         %[[val_26:.*]] = math.fma %[[val_25]], %[[cst_26]], %[[val_23]] : f32
+// CHECK-NEXT:         %[[val_23:.*]] = arith.negf %[[val_2]] : f32
+// CHECK-NEXT:         %[[val_24:.*]] = math.fma %[[val_22]], %[[val_23]], %[[cst_23]] : f32
+// CHECK-NEXT:         %[[val_25:.*]] = arith.subf %[[val_19]], %[[val_22]] : f32
+// CHECK-NEXT:         %[[val_26:.*]] = math.fma %[[val_24]], %[[cst_26]], %[[val_25]] : f32
 // CHECK-NEXT:         %[[val_27:.*]] = math.fma %[[val_26]], %[[val_21]], %[[val_22]] : f32
 // CHECK-NEXT:         %[[val_28:.*]] = arith.mulf %[[val_2]], %[[val_2]] : f32
 // CHECK-NEXT:         %[[val_29:.*]] = arith.negf %[[val_28]] : f32