lib: Add mlibc

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/lib/mlibc/options/lsb/generic/tls.cpp b/lib/mlibc/options/lsb/generic/tls.cpp
new file mode 100644
index 0000000..1d7cc30
--- /dev/null
+++ b/lib/mlibc/options/lsb/generic/tls.cpp
@@ -0,0 +1,23 @@
+#include <internal-config.h>
+#include <mlibc/thread.hpp>
+#include <mlibc/rtdl-abi.hpp>
+
+#if defined(__riscv) && defined(MLIBC_STATIC_BUILD)
+	// On RISC-V, linker optimisation is not guaranteed and so we may still get
+	// calls to this function in statically linked binaries.
+	// TODO: This will break dlopen calls from statically linked programs.
+	extern "C" void *__tls_get_addr(struct __abi_tls_entry *entry) {
+		Tcb *tcbPtr = mlibc::get_current_tcb();
+		auto dtvPtr = reinterpret_cast<char *>(tcbPtr->dtvPointers[0]);
+		return reinterpret_cast<void *>(dtvPtr + entry->offset + TLS_DTV_OFFSET);
+	}
+#elif defined(__i386__)
+	extern "C" __attribute__((regparm(1))) void *___tls_get_addr(struct __abi_tls_entry *entry) {
+		return __dlapi_get_tls(entry);
+	}
+#else
+	extern "C" void *__tls_get_addr(struct __abi_tls_entry *entry) {
+		return __dlapi_get_tls(entry);
+	}
+#endif
+