feat: allow users to check cpu flags (#1631)

allow users to check if specific cpu flags are supported by the host.

```yaml
apiVersion: troubleshoot.sh/v1beta2
kind: HostPreflight
metadata:
  name: ec-cluster-preflight
spec:
  collectors:
  - cpu: {}
  analyzers:
  - cpu:
      checkName: CPU
      outcomes:
        - pass:
            when: hasFlags cmov,cx8,fpu,fxsr,mmx
            message: CPU supports all required flags
        - fail:
            message: CPU not supported
```

Author: ricardomaraschini

pkg/analyze/host_cpu.go

@@ -15,14 +15,12 @@ import (
 // ref: https://gitlab.com/x86-psABIs/x86-64-ABI
 // ref: https://developers.redhat.com/blog/2021/01/05/building-red-hat-enterprise-linux-9-for-the-x86-64-v2-microarchitecture-level
 var microarchs = map[string][]string{
+	"x86-64":    {"cmov", "cx8", "fpu", "fxsr", "mmx", "syscall", "sse", "sse2"},
 	"x86-64-v2": {"cx16", "lahf_lm", "popcnt", "ssse3", "sse4_1", "sse4_2", "ssse3"},
 	"x86-64-v3": {"avx", "avx2", "bmi1", "bmi2", "f16c", "fma", "lzcnt", "movbe", "xsave"},
 	"x86-64-v4": {"avx512f", "avx512bw", "avx512cd", "avx512dq", "avx512vl"},
 }
 
-// x8664BaseFeatures are the features that are present in all x86-64 microarchitectures.
-var x8664BaseFeatures = []string{"cmov", "cx8", "fpu", "fxsr", "mmx", "syscall", "sse", "sse2"}
-
 type AnalyzeHostCPU struct {
 	hostAnalyzer *troubleshootv1beta2.CPUAnalyze
 }
@@ -126,13 +124,36 @@ func (a *AnalyzeHostCPU) Analyze(
 }
 
 func doCompareHostCPUMicroArchitecture(microarch string, flags []string) (res bool, err error) {
-	specifics, ok := microarchs[microarch]
-	if !ok && microarch != "x86-64" {
+	specifics := make([]string, 0)
+	switch microarch {
+	case "x86-64-v4":
+		specifics = append(specifics, microarchs["x86-64-v4"]...)
+		fallthrough
+	case "x86-64-v3":
+		specifics = append(specifics, microarchs["x86-64-v3"]...)
+		fallthrough
+	case "x86-64-v2":
+		specifics = append(specifics, microarchs["x86-64-v2"]...)
+		fallthrough
+	case "x86-64":
+		specifics = append(specifics, microarchs["x86-64"]...)
+	default:
 		return false, errors.Errorf("troubleshoot does not yet support microarchitecture %q", microarch)
 	}
-	expectedFlags := x8664BaseFeatures
-	if len(specifics) > 0 {
-		expectedFlags = append(expectedFlags, specifics...)
+
+	for _, flag := range specifics {
+		if slices.Contains(flags, flag) {
+			continue
+		}
+		return false, nil
+	}
+	return true, nil
+}
+
+func doCompareHostCPUFlags(expected string, flags []string) (res bool, err error) {
+	expectedFlags := strings.Split(expected, ",")
+	if len(expectedFlags) == 0 {
+		return false, errors.New("expected flags cannot be empty")
 	}
 	for _, flag := range expectedFlags {
 		if slices.Contains(flags, flag) {
@@ -173,6 +194,11 @@ func compareHostCPUConditionalToActual(conditional string, logicalCount int, phy
 		return doCompareHostCPUMicroArchitecture(desired, flags)
 	}
 
+	// hasFlags allows users to query for specific flags on the CPU.
+	if strings.ToLower(comparator) == "hasflags" {
+		return doCompareHostCPUFlags(desired, flags)
+	}
+
 	if !compareLogical && !comparePhysical && !compareUnspecified {
 		return false, errors.New("unable to parse conditional")
 	}

pkg/analyze/host_cpu_test.go

@@ -152,6 +152,18 @@ func Test_compareHostCPUConditionalToActual(t *testing.T) {
 			flags:    []string{"cmov", "cx8", "fpu", "fxsr", "mmx", "syscall", "sse", "sse2", "cx16", "lahf_lm", "popcnt", "ssse3", "sse4_1", "sse4_2", "ssse3"},
 			expected: true,
 		},
+		{
+			name:     "has a non existent flag",
+			when:     "hasFlags cmov,doesNotExist",
+			flags:    []string{"cmov", "cx8", "fpu", "fxsr", "mmx", "syscall", "sse", "sse2", "cx16", "lahf_lm", "popcnt", "ssse3", "sse4_1", "sse4_2", "ssse3"},
+			expected: false,
+		},
+		{
+			name:     "has flags",
+			when:     "hasFlags a,b,c",
+			flags:    []string{"a", "b", "c", "d", "e"},
+			expected: true,
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {