[AArch64] Add support for Armv9.6-A FEAT_SPE_EXC and FEAT_TRBE_EXC (#113463)

Add support for the following Armv9.6-A architecture extensions:
  * FEAT_SPE_EXC  - Statistical Profiling Extension profiling exceptions
  * FEAT_TRBE_EXC - Trace Buffer Management Events profiling exceptions

as documented here:

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

Co-authored-by: Jonathan Thackray <[email protected]>

Author: jwestwood921

llvm/lib/Target/AArch64/AArch64SystemOperands.td

@@ -2048,3 +2048,16 @@ let Requires = [{ {AArch64::FeaturePCDPHINT} }] in {
 
 // v9.6a Realm management extension enhancements
 def : RWSysReg<"GPCBW_EL3", 0b11, 0b110, 0b0010, 0b0001, 0b101>;
+
+// v9.6a Statistical Profiling Extension exception registers (FEAT_SPE_EXC)
+//                                Op0   Op1    CRn     CRm     Op2
+def : RWSysReg<"PMBMAR_EL1",      0b11, 0b000, 0b1001, 0b1010, 0b101>;
+def : RWSysReg<"PMBSR_EL12",      0b11, 0b101, 0b1001, 0b1010, 0b011>;
+def : RWSysReg<"PMBSR_EL2",       0b11, 0b100, 0b1001, 0b1010, 0b011>;
+def : RWSysReg<"PMBSR_EL3",       0b11, 0b110, 0b1001, 0b1010, 0b011>;
+
+// v9.6a Trace Buffer Management Events exception registers (FEAT_TRBE_EXC)
+//                                Op0   Op1    CRn     CRm     Op2
+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>;

llvm/test/MC/AArch64/armv9.6a-statistical-profiling.s

@@ -0,0 +1,19 @@
+// RUN: llvm-mc -triple aarch64-none-linux-gnu -show-encoding     < %s 2> %t | FileCheck %s
+
+  msr pmbmar_el1, x0
+  msr pmbsr_el12, x0
+  msr pmbsr_el2, x0
+  msr pmbsr_el3, x0
+// CHECK:     msr PMBMAR_EL1, x0          // encoding: [0xa0,0x9a,0x18,0xd5]
+// CHECK:     msr PMBSR_EL12, x0          // encoding: [0x60,0x9a,0x1d,0xd5]
+// CHECK:     msr PMBSR_EL2, x0           // encoding: [0x60,0x9a,0x1c,0xd5]
+// CHECK:     msr PMBSR_EL3, x0           // encoding: [0x60,0x9a,0x1e,0xd5]
+
+  mrs x0, pmbmar_el1
+  mrs x0, pmbsr_el12
+  mrs x0, pmbsr_el2
+  mrs x0, pmbsr_el3
+// CHECK:    mrs x0, PMBMAR_EL1          // encoding: [0xa0,0x9a,0x38,0xd5]
+// CHECK:    mrs x0, PMBSR_EL12          // encoding: [0x60,0x9a,0x3d,0xd5]
+// CHECK:    mrs x0, PMBSR_EL2           // encoding: [0x60,0x9a,0x3c,0xd5]
+// CHECK:    mrs x0, PMBSR_EL3           // encoding: [0x60,0x9a,0x3e,0xd5]

llvm/test/MC/AArch64/armv9.6a-trbe-exception.s

@@ -0,0 +1,15 @@
+// RUN: llvm-mc -triple aarch64-none-linux-gnu -show-encoding      < %s 2> %t | FileCheck %s
+
+  msr trbsr_el12, x0
+  msr trbsr_el2, x0
+  msr trbsr_el3, x0
+// CHECK:     msr TRBSR_EL12, x0          // encoding: [0x60,0x9b,0x1d,0xd5]
+// CHECK:     msr TRBSR_EL2, x0           // encoding: [0x60,0x9b,0x1c,0xd5]
+// CHECK:     msr TRBSR_EL3, x0           // encoding: [0x60,0x9b,0x1e,0xd5]
+
+  mrs x0, trbsr_el12
+  mrs x0, trbsr_el2
+  mrs x0, trbsr_el3
+// CHECK:    mrs x0, TRBSR_EL12          // encoding: [0x60,0x9b,0x3d,0xd5]
+// CHECK:    mrs x0, TRBSR_EL2           // encoding: [0x60,0x9b,0x3c,0xd5]
+// CHECK:    mrs x0, TRBSR_EL3           // encoding: [0x60,0x9b,0x3e,0xd5]

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

@@ -0,0 +1,15 @@
+# RUN: llvm-mc -triple aarch64 -disassemble < %s | FileCheck %s
+
+[0x60,0x9a,0x1d,0xd5]
+# CHECK: msr PMBSR_EL12, x0
+[0x60,0x9a,0x1c,0xd5]
+# CHECK: msr PMBSR_EL2, x0
+[0x60,0x9a,0x1e,0xd5]
+# CHECK: msr PMBSR_EL3, x0
+
+[0x60,0x9a,0x3d,0xd5]
+# CHECK: mrs x0, PMBSR_EL12
+[0x60,0x9a,0x3c,0xd5]
+# CHECK: mrs x0, PMBSR_EL2
+[0x60,0x9a,0x3e,0xd5]
+# CHECK: mrs x0, PMBSR_EL3

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

@@ -0,0 +1,15 @@
+# RUN: llvm-mc -triple aarch64 -disassemble < %s | FileCheck %s
+
+[0x60,0x9b,0x1d,0xd5]
+# CHECK: msr TRBSR_EL12, x0
+[0x60,0x9b,0x1c,0xd5]
+# CHECK: msr TRBSR_EL2, x0
+[0x60,0x9b,0x1e,0xd5]
+# CHECK: msr TRBSR_EL3, x0
+
+[0x60,0x9b,0x3d,0xd5]
+# CHECK: mrs x0, TRBSR_EL12
+[0x60,0x9b,0x3c,0xd5]
+# CHECK: mrs x0, TRBSR_EL2
+[0x60,0x9b,0x3e,0xd5]
+# CHECK: mrs x0, TRBSR_EL3