/* Target-dependent code for GNU/Linux on RISC-V processors.
- Copyright (C) 2018 Free Software Foundation, Inc.
+ Copyright (C) 2018-2020 Free Software Foundation, Inc.
This file is part of GDB.
#include "linux-tdep.h"
#include "solib-svr4.h"
#include "regset.h"
+#include "tramp-frame.h"
+#include "trad-frame.h"
+#include "gdbarch.h"
/* Define the general register mapping. The kernel puts the PC at offset 0,
gdb puts it at offset 32. Register x0 is always 0 and can be ignored.
{ 0 }
};
+/* Define the FP register mapping. The kernel puts the 32 FP regs first, and
+ then FCSR. */
+
+static const struct regcache_map_entry riscv_linux_fregmap[] =
+{
+ { 32, RISCV_FIRST_FP_REGNUM, 0 },
+ { 1, RISCV_CSR_FCSR_REGNUM, 0 },
+ { 0 }
+};
+
/* Define the general register regset. */
static const struct regset riscv_linux_gregset =
riscv_linux_gregmap, regcache_supply_regset, regcache_collect_regset
};
+/* Define the FP register regset. */
+
+static const struct regset riscv_linux_fregset =
+{
+ riscv_linux_fregmap, regcache_supply_regset, regcache_collect_regset
+};
+
/* Define hook for core file support. */
static void
void *cb_data,
const struct regcache *regcache)
{
- cb (".reg", (32 * riscv_isa_xlen (gdbarch)),
+ cb (".reg", (32 * riscv_isa_xlen (gdbarch)), (32 * riscv_isa_xlen (gdbarch)),
&riscv_linux_gregset, NULL, cb_data);
+ /* The kernel is adding 8 bytes for FCSR. */
+ cb (".reg2", (32 * riscv_isa_flen (gdbarch)) + 8,
+ (32 * riscv_isa_flen (gdbarch)) + 8,
+ &riscv_linux_fregset, NULL, cb_data);
+}
+
+/* Signal trampoline support. */
+
+static void riscv_linux_sigframe_init (const struct tramp_frame *self,
+ struct frame_info *this_frame,
+ struct trad_frame_cache *this_cache,
+ CORE_ADDR func);
+
+#define RISCV_INST_LI_A7_SIGRETURN 0x08b00893
+#define RISCV_INST_ECALL 0x00000073
+
+static const struct tramp_frame riscv_linux_sigframe = {
+ SIGTRAMP_FRAME,
+ 4,
+ {
+ { RISCV_INST_LI_A7_SIGRETURN, ULONGEST_MAX },
+ { RISCV_INST_ECALL, ULONGEST_MAX },
+ { TRAMP_SENTINEL_INSN }
+ },
+ riscv_linux_sigframe_init,
+ NULL
+};
+
+/* Runtime signal frames look like this:
+ struct rt_sigframe {
+ struct siginfo info;
+ struct ucontext uc;
+ };
+
+ struct ucontext {
+ unsigned long __uc_flags;
+ struct ucontext *uclink;
+ stack_t uc_stack;
+ sigset_t uc_sigmask;
+ char __glibc_reserved[1024 / 8 - sizeof (sigset_t)];
+ mcontext_t uc_mcontext;
+ }; */
- /* TODO: Add FP register support. */
+#define SIGFRAME_SIGINFO_SIZE 128
+#define UCONTEXT_MCONTEXT_OFFSET 176
+
+static void
+riscv_linux_sigframe_init (const struct tramp_frame *self,
+ struct frame_info *this_frame,
+ struct trad_frame_cache *this_cache,
+ CORE_ADDR func)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ int xlen = riscv_isa_xlen (gdbarch);
+ int flen = riscv_isa_flen (gdbarch);
+ CORE_ADDR frame_sp = get_frame_sp (this_frame);
+ CORE_ADDR mcontext_base;
+ CORE_ADDR regs_base;
+
+ mcontext_base = frame_sp + SIGFRAME_SIGINFO_SIZE + UCONTEXT_MCONTEXT_OFFSET;
+
+ /* Handle the integer registers. The first one is PC, followed by x1
+ through x31. */
+ regs_base = mcontext_base;
+ trad_frame_set_reg_addr (this_cache, RISCV_PC_REGNUM, regs_base);
+ for (int i = 1; i < 32; i++)
+ trad_frame_set_reg_addr (this_cache, RISCV_ZERO_REGNUM + i,
+ regs_base + (i * xlen));
+
+ /* Handle the FP registers. First comes the 32 FP registers, followed by
+ fcsr. */
+ regs_base += 32 * xlen;
+ for (int i = 0; i < 32; i++)
+ trad_frame_set_reg_addr (this_cache, RISCV_FIRST_FP_REGNUM + i,
+ regs_base + (i * flen));
+ regs_base += 32 * flen;
+ trad_frame_set_reg_addr (this_cache, RISCV_CSR_FCSR_REGNUM, regs_base);
+
+ /* Choice of the bottom of the sigframe is somewhat arbitrary. */
+ trad_frame_set_id (this_cache, frame_id_build (frame_sp, func));
}
/* Initialize RISC-V Linux ABI info. */
set_gdbarch_iterate_over_regset_sections
(gdbarch, riscv_linux_iterate_over_regset_sections);
+
+ tramp_frame_prepend_unwinder (gdbarch, &riscv_linux_sigframe);
}
/* Initialize RISC-V Linux target support. */