[AArch64] Add support for Armv9.6-A FEAT_PoPS architecture extension (#113496)

Add support for the following Armv9.6-A architecture extensions:
  * FEAT_PoPS      - Point of Physical Storage

as documented here:

https://developer.arm.com/documentation/109697/2024_09/Feature-descriptions/The-Armv9-6-architecture-extension

Co-authored-by: Alfie Richards <[email protected]>

Author: jthackray

clang/test/Driver/aarch64-v96a.c

@@ -65,4 +65,8 @@
 // RUN: %clang -target aarch64 -march=armv9.6a+pcdphint -### -c %s 2>&1 | FileCheck -check-prefix=V96A-PCDPHINT %s
 // RUN: %clang -target aarch64 -march=armv9.6-a+pcdphint -### -c %s 2>&1 | FileCheck -check-prefix=V96A-PCDPHINT %s
 // V96A-PCDPHINT: "-cc1"{{.*}} "-triple" "aarch64{{.*}}" "-target-cpu" "generic" "-target-feature" "+v9.6a"{{.*}} "-target-feature" "+pcdphint"
+
+// RUN: %clang -target aarch64 -march=armv9.6a+pops -### -c %s 2>&1 | FileCheck -check-prefix=V96A-POPS %s
+// RUN: %clang -target aarch64 -march=armv9.6-a+pops -### -c %s 2>&1 | FileCheck -check-prefix=V96A-POPS %s
+// V96A-POPS: "-cc1"{{.*}} "-triple" "aarch64{{.*}}" "-target-cpu" "generic" "-target-feature" "+v9.6a"{{.*}} "-target-feature" "+pops"
 //

clang/test/Driver/print-supported-extensions-aarch64.c

@@ -50,6 +50,7 @@
 // CHECK-NEXT:     pauth-lr            FEAT_PAuth_LR                                          Enable Armv9.5-A PAC enhancements
 // CHECK-NEXT:     pcdphint            FEAT_PCDPHINT                                          Enable Armv9.6-A Producer Consumer Data Placement hints
 // CHECK-NEXT:     pmuv3               FEAT_PMUv3                                             Enable Armv8.0-A PMUv3 Performance Monitors extension
+// CHECK-NEXT:     pops                FEAT_PoPS                                              Enable Armv9.6-A Point Of Physical Storage (PoPS) DC instructions
 // CHECK-NEXT:     predres             FEAT_SPECRES                                           Enable Armv8.5-A execution and data prediction invalidation instructions
 // CHECK-NEXT:     rng                 FEAT_RNG                                               Enable Random Number generation instructions
 // CHECK-NEXT:     ras                 FEAT_RAS, FEAT_RASv1p1                                 Enable Armv8.0-A Reliability, Availability and Serviceability Extensions

llvm/lib/Target/AArch64/AArch64Features.td

@@ -565,6 +565,9 @@ def FeatureOCCMO: ExtensionWithMArch<"occmo", "OCCMO", "FEAT_OCCMO",
 def FeaturePCDPHINT: ExtensionWithMArch<"pcdphint", "PCDPHINT", "FEAT_PCDPHINT",
   "Enable Armv9.6-A Producer Consumer Data Placement hints">;
 
+def FeaturePoPS: ExtensionWithMArch<"pops", "PoPS", "FEAT_PoPS",
+  "Enable Armv9.6-A Point Of Physical Storage (PoPS) DC instructions">;
+
 //===----------------------------------------------------------------------===//
 //  Other Features
 //===----------------------------------------------------------------------===//

llvm/lib/Target/AArch64/AArch64SystemOperands.td

@@ -2061,3 +2061,10 @@ def : RWSysReg<"PMBSR_EL3",       0b11, 0b110, 0b1001, 0b1010, 0b011>;
 def : RWSysReg<"TRBSR_EL12",      0b11, 0b101, 0b1001, 0b1011, 0b011>;
 def : RWSysReg<"TRBSR_EL2",       0b11, 0b100, 0b1001, 0b1011, 0b011>;
 def : RWSysReg<"TRBSR_EL3",       0b11, 0b110, 0b1001, 0b1011, 0b011>;
+
+// v9.6 FEAT_PoPS
+//
+let Requires = [{ {AArch64::FeaturePoPS} }] in {
+def : DC<"CIGDVAPS",  0b000, 0b0111, 0b1111, 0b101>;
+def : DC<"CIVAPS",    0b000, 0b0111, 0b1111, 0b001>;
+}

llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp

@@ -3794,6 +3794,7 @@ static const struct Extension {
     {"sme-fa64", {AArch64::FeatureSMEFA64}},
     {"cpa", {AArch64::FeatureCPA}},
     {"tlbiw", {AArch64::FeatureTLBIW}},
+    {"pops", {AArch64::FeaturePoPS}},
     {"cmpbr", {AArch64::FeatureCMPBR}},
     {"f8f32mm", {AArch64::FeatureF8F32MM}},
     {"f8f16mm", {AArch64::FeatureF8F16MM}},

llvm/test/MC/AArch64/armv9.6a-ras.s

@@ -0,0 +1,12 @@
+// RUN: not llvm-mc -triple aarch64 -show-encoding < %s 2>&1 | FileCheck %s --check-prefix NO-POPS
+// RUN: llvm-mc -triple aarch64 -mattr=+pops -show-encoding < %s 2>&1 | FileCheck %s --check-prefix HAS-POPS
+
+dc CIGDVAPS, x3
+dc CIVAPS, x3
+// NO-POPS: error: DC CIGDVAPS requires: pops
+// NO-POPS: error: DC CIVAPS requires: pops
+
+# HAS-POPS:      	.text
+
+# HAS-POPS:      	dc	cigdvaps, x3                    // encoding: [0xa3,0x7f,0x08,0xd5]
+# HAS-POPS-NEXT: 	dc	civaps, x3                      // encoding: [0x23,0x7f,0x08,0xd5]

llvm/test/MC/Disassembler/AArch64/armv9.6a-ras.txt

@@ -0,0 +1,11 @@
+# RUN: llvm-mc -triple aarch64 -mattr=+pops -disassemble < %s | FileCheck %s
+
+#------------------------------------------------------------------------------
+# ARMV9.6-A RAS Extensions
+#------------------------------------------------------------------------------
+
+[0xa3,0x7f,0x08,0xd5]
+# CHECK: dc cigdvaps, x3
+
+[0x23,0x7f,0x08,0xd5]
+# CHECK: dc civaps, x3

llvm/unittests/TargetParser/TargetParserTest.cpp

@@ -1333,7 +1333,7 @@ TEST(TargetParserTest, AArch64ExtensionFeatures) {
       AArch64::AEK_F8F16MM,      AArch64::AEK_LSFE,
       AArch64::AEK_FPRCVT,       AArch64::AEK_CMPBR,
       AArch64::AEK_LSUI,         AArch64::AEK_OCCMO,
-      AArch64::AEK_PCDPHINT,
+      AArch64::AEK_PCDPHINT,     AArch64::AEK_POPS,
   };
 
   std::vector<StringRef> Features;
@@ -1437,6 +1437,7 @@ TEST(TargetParserTest, AArch64ExtensionFeatures) {
   EXPECT_TRUE(llvm::is_contained(Features, "+lsui"));
   EXPECT_TRUE(llvm::is_contained(Features, "+occmo"));
   EXPECT_TRUE(llvm::is_contained(Features, "+pcdphint"));
+  EXPECT_TRUE(llvm::is_contained(Features, "+pops"));
 
   // Assuming we listed every extension above, this should produce the same
   // result.
@@ -1592,6 +1593,7 @@ TEST(TargetParserTest, AArch64ArchExtFeature) {
       {"lsui", "nolsui", "+lsui", "-lsui"},
       {"occmo", "nooccmo", "+occmo", "-occmo"},
       {"pcdphint", "nopcdphint", "+pcdphint", "-pcdphint"},
+      {"pops", "nopops", "+pops", "-pops"},
   };
 
   for (unsigned i = 0; i < std::size(ArchExt); i++) {