[AArch64] Add command line support for v9.4-A's Instrumentation Extension

[pratlucas]

Summary

This introduces command line support (+ite) for the v9.4-A's
Instrumentation Extension (FEAT_ITE).

Patch by Son Tuan Vu.

[pratlucas]

Rebasing, including minor changes due to recent target parser refactoring.

clang/test/Driver/aarch64-ite.c

+// Test that target feature ite is implemented and available correctly
+
+// FEAT_ITE is optional (off by default) for v8.9a/9.4a and older, and can be enabled using +ite
+// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.8-a       %s 2>&1 | FileCheck %s --check-prefix=NOT_ENABLED
+// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.8-a+ite   %s 2>&1 | FileCheck %s --check-prefix=ENABLED
+// RUN: %clang -### -target aarch64-none-none-eabi -march=armv8.8-a+noite %s 2>&1 | FileCheck %s --check-prefix=DISABLED
+// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.3-a       %s 2>&1 | FileCheck %s --check-prefix=NOT_ENABLED
+// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.3-a+ite   %s 2>&1 | FileCheck %s --check-prefix=ENABLED
+// RUN: %clang -### -target aarch64-none-none-eabi -march=armv9.3-a+noite %s 2>&1 | FileCheck %s --check-prefix=DISABLED
+
+// FEAT_ITE is invalid before v8
+// RUN: %clang -### -target arm-none-none-eabi -march=armv7-a+ite     %s 2>&1 | FileCheck %s --check-prefix=INVALID
+
+// INVALID: error: unsupported argument 'armv7-a+ite' to option '-march='
+// ENABLED: "-target-feature" "+ite"
+// NOT_ENABLED-NOT: "-target-feature" "+ite"
+// DISABLED: "-target-feature" "-ite"

llvm/include/llvm/TargetParser/AArch64TargetParser.h

enum ArchExtKind : uint64_t {
   AEK_SMEF16F16 =   1ULL << 47, // FEAT_SMEF16F16
   AEK_CSSC =        1ULL << 48, // FEAT_CSSC
   AEK_RCPC3 =       1ULL << 49, // FEAT_LRCPC3
   AEK_THE =         1ULL << 50, // FEAT_THE
   AEK_D128 =        1ULL << 51, // FEAT_D128
   AEK_LSE128 =      1ULL << 52, // FEAT_LSE128
   AEK_SPECRES2 =    1ULL << 53, // FEAT_SPECRES2
   AEK_RASv2 =       1ULL << 54, // FEAT_RASv2
+  AEK_ITE =         1ULL << 55, // FEAT_ITE
 };
 // clang-format on
 
 // Represents an extension that can be enabled with -march=<arch>+<extension>.
 // Typically these correspond to Arm Architecture extensions, unlike
 // SubtargetFeature which may represent either an actual extension or some
 // internal LLVM property.
 struct ExtensionInfo {
inline constexpr ExtensionInfo Extensions[] = {
     {"flagm", AArch64::AEK_FLAGM, "+flagm", "-flagm", FEAT_FLAGM, "+flagm", 20},
     {"flagm2", AArch64::AEK_NONE, {}, {}, FEAT_FLAGM2, "+flagm,+altnzcv", 30},
     {"fp", AArch64::AEK_FP, "+fp-armv8", "-fp-armv8", FEAT_FP, "+fp-armv8,+neon", 90},
     {"fp16", AArch64::AEK_FP16, "+fullfp16", "-fullfp16", FEAT_FP16, "+fullfp16,+fp-armv8,+neon", 170},
     {"fp16fml", AArch64::AEK_FP16FML, "+fp16fml", "-fp16fml", FEAT_FP16FML, "+fp16fml,+fullfp16,+fp-armv8,+neon", 40},
     {"frintts", AArch64::AEK_NONE, {}, {}, FEAT_FRINTTS, "+fptoint", 250},
     {"hbc", AArch64::AEK_HBC, "+hbc", "-hbc", FEAT_MAX, "", 0},
     {"i8mm", AArch64::AEK_I8MM, "+i8mm", "-i8mm", FEAT_I8MM, "+i8mm", 270},
+    {"ite", AArch64::AEK_ITE, "+ite", "-ite", FEAT_MAX, "", 0},
     {"jscvt", AArch64::AEK_NONE, {}, {}, FEAT_JSCVT, "+fp-armv8,+neon,+jsconv", 210},
     {"ls64_accdata", AArch64::AEK_NONE, {}, {}, FEAT_LS64_ACCDATA, "+ls64", 540},
     {"ls64_v", AArch64::AEK_NONE, {}, {}, FEAT_LS64_V, "", 530},
     {"ls64", AArch64::AEK_LS64, "+ls64", "-ls64", FEAT_LS64, "", 520},
     {"lse", AArch64::AEK_LSE, "+lse", "-lse", FEAT_LSE, "+lse", 80},
     {"lse128", AArch64::AEK_LSE128, "+lse128", "-lse128", FEAT_MAX, "", 0},
     {"memtag", AArch64::AEK_MTE, "+mte", "-mte", FEAT_MEMTAG, "", 440},
     {"memtag2", AArch64::AEK_NONE, {}, {}, FEAT_MEMTAG2, "+mte", 450},

llvm/unittests/TargetParser/TargetParserTest.cpp

std::vector<uint64_t> Extensions = {
       AArch64::AEK_F64MM,   AArch64::AEK_TME,       AArch64::AEK_LS64,
       AArch64::AEK_BRBE,    AArch64::AEK_PAUTH,     AArch64::AEK_FLAGM,
       AArch64::AEK_SME,     AArch64::AEK_SMEF64F64, AArch64::AEK_SMEI16I64,
       AArch64::AEK_SME2,    AArch64::AEK_HBC,       AArch64::AEK_MOPS,
       AArch64::AEK_PERFMON, AArch64::AEK_SVE2p1,    AArch64::AEK_SME2p1,
       AArch64::AEK_B16B16,  AArch64::AEK_SMEF16F16, AArch64::AEK_CSSC,
       AArch64::AEK_RCPC3,   AArch64::AEK_THE,       AArch64::AEK_D128,
       AArch64::AEK_LSE128,  AArch64::AEK_SPECRES2,  AArch64::AEK_RASv2,
+      AArch64::AEK_ITE,
   };
 
   std::vector<StringRef> Features;
 
   uint64_t ExtVal = 0;
   for (auto Ext : Extensions)
     ExtVal |= Ext;
 
TEST(TargetParserTest, AArch64ExtensionFeatures) {
   EXPECT_TRUE(llvm::is_contained(Features, "+mops"));
   EXPECT_TRUE(llvm::is_contained(Features, "+perfmon"));
   EXPECT_TRUE(llvm::is_contained(Features, "+cssc"));
   EXPECT_TRUE(llvm::is_contained(Features, "+rcpc3"));
   EXPECT_TRUE(llvm::is_contained(Features, "+the"));
   EXPECT_TRUE(llvm::is_contained(Features, "+d128"));
   EXPECT_TRUE(llvm::is_contained(Features, "+lse128"));
   EXPECT_TRUE(llvm::is_contained(Features, "+specres2"));
+  EXPECT_TRUE(llvm::is_contained(Features, "+ite"));
 
   // Assuming we listed every extension above, this should produce the same
   // result. (note that AEK_NONE doesn't have a name so it won't be in the
   // result despite its bit being set)
   std::vector<StringRef> AllFeatures;
   EXPECT_TRUE(AArch64::getExtensionFeatures(-1, AllFeatures));
   EXPECT_THAT(Features, ::testing::ContainerEq(AllFeatures));
 }