1 files changed, 132 insertions, 0 deletions
diff --git a/src/loongarch64/Gresume.c b/src/loongarch64/Gresume.c
new file mode 100644
index 00000000..9a9c717e
--- /dev/null
+++ b/src/loongarch64/Gresume.c
@@ -0,0 +1,132 @@
+/* libunwind - a platform-independent unwind library
+   Copyright (C) 2008 CodeSourcery
+   Copyright (C) 2021 Loongson Technology Corporation Limited
+
+This file is part of libunwind.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
+
+/* FIXME for LoongArch64.  */
+
+#include <stdlib.h>
+
+#include "unwind_i.h"
+
+#ifndef UNW_REMOTE_ONLY
+
+HIDDEN inline int
+loongarch64_local_resume (unw_addr_space_t as, unw_cursor_t *cursor, void *arg)
+{
+  struct cursor *c = (struct cursor *) cursor;
+  unw_tdep_context_t *uc = c->uc;
+
+  if (c->sigcontext_format == LOONGARCH64_SCF_NONE)
+    {
+      /* Since there are no signals involved here we restore EH and non scratch
+         registers only.  */
+      unsigned long sp = uc->uc_mcontext.__gregs[3];
+      unsigned long ra = uc->uc_mcontext.__gregs[1];
+
+      asm volatile (
+        "move $t0, %0\n"
+        "move $t1, %1\n"
+        "move $t2, %2\n"
+        "ld.d $fp, $t0, 22*8\n"
+        "ld.d $s0, $t0, 23*8\n"
+        "ld.d $s1, $t0, 24*8\n"
+        "ld.d $s2, $t0, 25*8\n"
+        "ld.d $s3, $t0, 26*8\n"
+        "ld.d $s4, $t0, 27*8\n"
+        "ld.d $s5, $t0, 28*8\n"
+        "ld.d $s6, $t0, 29*8\n"
+        "ld.d $s7, $t0, 30*8\n"
+        "ld.d $s8, $t0, 31*8\n"
+        "move $ra, $t2\n"
+        "move $sp, $t1\n"
+        "jirl $r0, $ra, 0\n"
+        :
+        : "r" (uc->uc_mcontext.__gregs),
+          "r" (sp),
+          "r" (ra)
+      );
+    }
+  else /* c->sigcontext_format == LOONGARCH64_SCF_LINUX_RT_SIGFRAME */
+    {
+      int i;
+      struct sigcontext *sc = (struct sigcontext *) c->sigcontext_addr;
+
+      sc->sc_pc = c->dwarf.ip;
+      for (i = UNW_LOONGARCH64_R0; i <= UNW_LOONGARCH64_R31; i++)
+            sc->sc_regs[i] = uc->uc_mcontext.__gregs[i];
+
+      Debug (8, "resuming at ip=0x%lx via sigreturn() (trampoline @ 0x%lx, sp @ 0x%lx)\n",
+        c->dwarf.ip, c->sigcontext_pc, c->sigcontext_sp);
+
+      asm volatile (
+        "move $sp, %0\n"
+        "jirl $r0, %1, 0\n"
+        : : "r" (c->sigcontext_sp), "r" (c->sigcontext_pc)
+      );
+   }
+  unreachable();
+
+  return -UNW_EINVAL;
+}
+
+#endif /* !UNW_REMOTE_ONLY */
+
+static inline void
+establish_machine_state (struct cursor *c)
+{
+  unw_addr_space_t as = c->dwarf.as;
+  void *arg = c->dwarf.as_arg;
+  unw_word_t val;
+  int reg;
+
+  Debug (8, "copying out cursor state\n");
+
+  for (reg = UNW_LOONGARCH64_R0; reg <= UNW_LOONGARCH64_R31; reg++)
+    {
+      Debug (16, "copying %s %d\n", unw_regname (reg), reg);
+      if (tdep_access_reg (c, reg, &val, 0) >= 0)
+        as->acc.access_reg (as, reg, &val, 1, arg);
+    }
+}
+
+int
+unw_resume (unw_cursor_t *cursor)
+{
+  struct cursor *c = (struct cursor *) cursor;
+
+  Debug (1, "(cursor=%p)\n", c);
+
+  if (!c->dwarf.ip)
+    {
+      /* This can happen easily when the frame-chain gets truncated
+         due to bad or missing unwind-info.  */
+      Debug (1, "refusing to resume execution at address 0\n");
+      return -UNW_EINVAL;
+    }
+
+  establish_machine_state (c);
+
+  return (*c->dwarf.as->acc.resume) (c->dwarf.as, (unw_cursor_t *) c,
+                                     c->dwarf.as_arg);
+}