================
@@ -93,6 +93,55 @@ DNBArchMachARM64::SoftwareBreakpointOpcode(nub_size_t
byte_size) {
uint32_t DNBArchMachARM64::GetCPUType() { return CPU_TYPE_ARM64; }
+static std::once_flag g_cpu_has_sme_once;
+bool DNBArchMachARM64::CPUHasSME() {
+ static bool g_has_sme = false;
+ std::call_once(g_cpu_has_sme_once, []() {
+ int ret = 0;
+ size_t size = sizeof(ret);
+ if (sysctlbyname("hw.optional.arm.FEAT_SME", &ret, &size, NULL, 0) != -1)
+ g_has_sme = ret == 1;
+ });
+ return g_has_sme;
+}
+
+static std::once_flag g_cpu_has_sme2_once;
+bool DNBArchMachARM64::CPUHasSME2() {
+ static bool g_has_sme2 = false;
+ std::call_once(g_cpu_has_sme2_once, []() {
+ int ret = 0;
+ size_t size = sizeof(ret);
+ if (sysctlbyname("hw.optional.arm.FEAT_SME2", &ret, &size, NULL, 0) != -1)
+ g_has_sme2 = ret == 1;
+ });
+ return g_has_sme2;
+}
+
+static std::once_flag g_sme_max_svl_once;
+unsigned int DNBArchMachARM64::GetSMEMaxSVL() {
+ static unsigned int g_sme_max_svl = 0;
+ std::call_once(g_sme_max_svl_once, []() {
+ if (CPUHasSME()) {
+ unsigned int ret = 0;
+ size_t size = sizeof(ret);
+ if (sysctlbyname("hw.optional.arm.sme_max_svl_b", &ret, &size, NULL, 0)
!=
+ -1)
+ g_sme_max_svl = ret;
+ else
+ g_sme_max_svl = get_svl_bytes();
+ }
+ });
+ return g_sme_max_svl;
+}
+
+// This function can only be called on systems with hw.optional.arm.FEAT_SME
+// It will return the maximum SVL length for this process.
+uint16_t __attribute__((target("sme"))) DNBArchMachARM64::get_svl_bytes(void) {
+ uint64_t ret = 0;
+ asm volatile("rdsvl %[ret], #1" : [ret] "=r"(ret));
----------------
DavidSpickett wrote:
Are you sure this is the maximum not the current?
https://developer.arm.com/documentation/ddi0602/2024-09/SME-Instructions/RDSVL--Read-multiple-of-Streaming-SVE-vector-register-size-to-scalar-register-
Though if the kernel doesn't have a way to change it, for Darwin, it will be
the maximum value. But strictly speaking.
https://github.com/llvm/llvm-project/pull/119171
_______________________________________________
lldb-commits mailing list
lldb-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
