[llvm] [ValueTracking] Implement `computeKnownFPClass` for `llvm.vector.reduce.{fmin,fmax,fmaximum,fminimum}` (PR #88408)

[Matt Arsenault via llvm-commits]

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@@ -1109,6 +1109,106 @@ define float @fcmp_ult_neginf_implies_class_assert(float %arg) {
   ret float %mul_by_zero
 }
 
+define i1 @isKnownNeverInfinity_vector_reduce_maximum(<4 x double> %x) {
+; CHECK-LABEL: define i1 @isKnownNeverInfinity_vector_reduce_maximum
+; CHECK-SAME: (<4 x double> [[X:%.*]]) {
+; CHECK-NEXT:    ret i1 true
+;
+  %ninf.x = fadd ninf <4 x double> %x, <double 1.0, double 1.0, double 1.0, double 1.0>
+  %op = call double @llvm.vector.reduce.fmaximum(<4 x double> %ninf.x)
+  %cmp = fcmp une double %op, 0x7ff0000000000000
+  ret i1 %cmp
+}
+
+define i1 @isKnownNeverInfinity_vector_reduce_maximum_fail(<4 x double> %x) {
+; CHECK-LABEL: define i1 @isKnownNeverInfinity_vector_reduce_maximum_fail
+; CHECK-SAME: (<4 x double> [[X:%.*]]) {
+; CHECK-NEXT:    [[NINF_X:%.*]] = fadd <4 x double> [[X]], <double 1.000000e+00, double 1.000000e+00, double 1.000000e+00, double 1.000000e+00>
+; CHECK-NEXT:    [[OP:%.*]] = call double @llvm.vector.reduce.fmaximum.v4f64(<4 x double> [[NINF_X]])
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[OP]], 0x7FF0000000000000
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %ninf.x = fadd <4 x double> %x, <double 1.0, double 1.0, double 1.0, double 1.0>
+  %op = call double @llvm.vector.reduce.fmaximum(<4 x double> %ninf.x)
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arsenm wrote:

Missing the .v4f64 

https://github.com/llvm/llvm-project/pull/88408