[LoopVectorize] add test for fmin/fmax FMF propagation; NFC

The existing test has less FMF than we might expect if
our FMF was fixed (on all FP values), so this additional
test is intended to check propagation in a more "normal"
example.

Author: rotateright

llvm/test/Transforms/LoopVectorize/X86/reduction-fastmath.ll

@@ -349,4 +349,89 @@ for.body:
   br i1 %exitcond, label %for.cond.cleanup, label %for.body
 }
 
+define float @PR35538_more_FMF(float* nocapture readonly %a, i32 %N) #0 {
+; CHECK-LABEL: @PR35538_more_FMF(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP12:%.*]] = icmp sgt i32 [[N:%.*]], 0
+; CHECK-NEXT:    br i1 [[CMP12]], label [[FOR_BODY_LR_PH:%.*]], label [[FOR_COND_CLEANUP:%.*]]
+; CHECK:       for.body.lr.ph:
+; CHECK-NEXT:    [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[N]] to i64
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[WIDE_TRIP_COUNT]], 8
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
+; CHECK:       vector.ph:
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[WIDE_TRIP_COUNT]], 8
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[WIDE_TRIP_COUNT]], [[N_MOD_VF]]
+; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]
+; CHECK:       vector.body:
+; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x float> [ <float -1.000000e+00, float -1.000000e+00, float -1.000000e+00, float -1.000000e+00>, [[VECTOR_PH]] ], [ [[TMP10:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[VEC_PHI1:%.*]] = phi <4 x float> [ <float -1.000000e+00, float -1.000000e+00, float -1.000000e+00, float -1.000000e+00>, [[VECTOR_PH]] ], [ [[TMP11:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 0
+; CHECK-NEXT:    [[TMP1:%.*]] = add i64 [[INDEX]], 4
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr inbounds float, float* [[A:%.*]], i64 [[TMP0]]
+; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr inbounds float, float* [[A]], i64 [[TMP1]]
+; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr inbounds float, float* [[TMP2]], i32 0
+; CHECK-NEXT:    [[TMP5:%.*]] = bitcast float* [[TMP4]] to <4 x float>*
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x float>, <4 x float>* [[TMP5]], align 4
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr inbounds float, float* [[TMP2]], i32 4
+; CHECK-NEXT:    [[TMP7:%.*]] = bitcast float* [[TMP6]] to <4 x float>*
+; CHECK-NEXT:    [[WIDE_LOAD2:%.*]] = load <4 x float>, <4 x float>* [[TMP7]], align 4
+; CHECK-NEXT:    [[TMP8:%.*]] = fcmp nnan ninf oge <4 x float> [[WIDE_LOAD]], [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP9:%.*]] = fcmp nnan ninf oge <4 x float> [[WIDE_LOAD2]], [[VEC_PHI1]]
+; CHECK-NEXT:    [[TMP10]] = select <4 x i1> [[TMP8]], <4 x float> [[WIDE_LOAD]], <4 x float> [[VEC_PHI]]
+; CHECK-NEXT:    [[TMP11]] = select <4 x i1> [[TMP9]], <4 x float> [[WIDE_LOAD2]], <4 x float> [[VEC_PHI1]]
+; CHECK-NEXT:    [[INDEX_NEXT]] = add i64 [[INDEX]], 8
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP12]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], [[LOOP10:!llvm.loop !.*]]
+; CHECK:       middle.block:
+; CHECK-NEXT:    [[RDX_MINMAX_CMP:%.*]] = fcmp fast ogt <4 x float> [[TMP10]], [[TMP11]]
+; CHECK-NEXT:    [[RDX_MINMAX_SELECT:%.*]] = select fast <4 x i1> [[RDX_MINMAX_CMP]], <4 x float> [[TMP10]], <4 x float> [[TMP11]]
+; CHECK-NEXT:    [[TMP13:%.*]] = call nnan ninf float @llvm.vector.reduce.fmax.v4f32(<4 x float> [[RDX_MINMAX_SELECT]])
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[WIDE_TRIP_COUNT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label [[FOR_COND_CLEANUP_LOOPEXIT:%.*]], label [[SCALAR_PH]]
+; CHECK:       scalar.ph:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_LR_PH]] ]
+; CHECK-NEXT:    [[BC_MERGE_RDX:%.*]] = phi float [ -1.000000e+00, [[FOR_BODY_LR_PH]] ], [ [[TMP13]], [[MIDDLE_BLOCK]] ]
+; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
+; CHECK:       for.cond.cleanup.loopexit:
+; CHECK-NEXT:    [[MAX_0__LCSSA:%.*]] = phi float [ [[MAX_0_:%.*]], [[FOR_BODY]] ], [ [[TMP13]], [[MIDDLE_BLOCK]] ]
+; CHECK-NEXT:    br label [[FOR_COND_CLEANUP]]
+; CHECK:       for.cond.cleanup:
+; CHECK-NEXT:    [[MAX_0_LCSSA:%.*]] = phi float [ -1.000000e+00, [[ENTRY:%.*]] ], [ [[MAX_0__LCSSA]], [[FOR_COND_CLEANUP_LOOPEXIT]] ]
+; CHECK-NEXT:    ret float [[MAX_0_LCSSA]]
+; CHECK:       for.body:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ], [ [[INDVARS_IV_NEXT:%.*]], [[FOR_BODY]] ]
+; CHECK-NEXT:    [[MAX_013:%.*]] = phi float [ [[BC_MERGE_RDX]], [[SCALAR_PH]] ], [ [[MAX_0_]], [[FOR_BODY]] ]
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds float, float* [[A]], i64 [[INDVARS_IV]]
+; CHECK-NEXT:    [[TMP14:%.*]] = load float, float* [[ARRAYIDX]], align 4
+; CHECK-NEXT:    [[CMP1_INV:%.*]] = fcmp nnan ninf oge float [[TMP14]], [[MAX_013]]
+; CHECK-NEXT:    [[MAX_0_]] = select nnan ninf i1 [[CMP1_INV]], float [[TMP14]], float [[MAX_013]]
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
+; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV_NEXT]], [[WIDE_TRIP_COUNT]]
+; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_COND_CLEANUP_LOOPEXIT]], label [[FOR_BODY]], [[LOOP11:!llvm.loop !.*]]
+;
+entry:
+  %cmp12 = icmp sgt i32 %N, 0
+  br i1 %cmp12, label %for.body.lr.ph, label %for.cond.cleanup
+
+for.body.lr.ph:
+  %wide.trip.count = zext i32 %N to i64
+  br label %for.body
+
+for.cond.cleanup:
+  %max.0.lcssa = phi float [ -1.000000e+00, %entry ], [ %max.0., %for.body ]
+  ret float %max.0.lcssa
+
+for.body:
+  %indvars.iv = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
+  %max.013 = phi float [ -1.000000e+00, %for.body.lr.ph ], [ %max.0., %for.body ]
+  %arrayidx = getelementptr inbounds float, float* %a, i64 %indvars.iv
+  %0 = load float, float* %arrayidx, align 4
+  %cmp1.inv = fcmp nnan ninf oge float %0, %max.013
+  %max.0. = select nnan ninf i1 %cmp1.inv, float %0, float %max.013
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count
+  br i1 %exitcond, label %for.cond.cleanup, label %for.body
+}
+
 attributes #0 = { "no-infs-fp-math"="true" "no-nans-fp-math"="true" "no-signed-zeros-fp-math"="false" "unsafe-fp-math"="false" }