Hi, Richard,
在 2013-05-24五的 14:20 -0700，Richard Henderson写道：
> Allows unwinding past the code_gen_buffer.
>
> Signed-off-by: Richard Henderson <r...@twiddle.net>
> ---
> tcg/arm/tcg-target.c | 91
> ++++++++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 82 insertions(+), 9 deletions(-)
>
> diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c
> index 3d43412..4a691b1 100644
> --- a/tcg/arm/tcg-target.c
> +++ b/tcg/arm/tcg-target.c
> @@ -2100,23 +2100,31 @@ static inline void tcg_out_movi(TCGContext *s,
> TCGType type,
> tcg_out_movi32(s, COND_AL, ret, arg);
> }
>
> +
> +typedef struct {
> + uint32_t len __attribute__((aligned((sizeof(void *)))));
> + uint32_t cie_offset;
> + tcg_target_long func_start __attribute__((packed));
> + tcg_target_long func_len __attribute__((packed));
suspicious usage of packed attribute here,
since tcg_targe_long is either 32 or 64 bits,
not a struct or union.
Thanks!
> + uint8_t def_cfa[4];
> + uint8_t reg_ofs[18];
> +} DebugFrameFDE;
> +
> +typedef struct {
> + DebugFrameCIE cie;
> + DebugFrameFDE fde;
> +} DebugFrame;
> +
> +#define ELF_HOST_MACHINE EM_ARM
> +
> +static DebugFrame debug_frame = {
> + .cie.len = sizeof(DebugFrameCIE)-4, /* length after .len member */
> + .cie.id = -1,
> + .cie.version = 1,
> + .cie.code_align = 1,
> + .cie.data_align = 0x7c, /* sleb128 -4 */
> + .cie.return_column = 14,
> +
> + .fde.len = sizeof(DebugFrameFDE)-4, /* length after .len member */
> + .fde.def_cfa = {
> + 12, 13, /* DW_CFA_def_cfa sp, ... */
> + (FRAME_SIZE & 0x7f) | 0x80, /* ... uleb128 FRAME_SIZE */
> + (FRAME_SIZE >> 7)
> + },
> + .fde.reg_ofs = {
> + /* The following must match the stmdb in the prologue. */
> + 0x8e, 1, /* DW_CFA_offset, lr, -4 */
> + 0x8b, 2, /* DW_CFA_offset, r11, -8 */
> + 0x8a, 3, /* DW_CFA_offset, r10, -12 */
> + 0x89, 4, /* DW_CFA_offset, r9, -16 */
> + 0x88, 5, /* DW_CFA_offset, r8, -20 */
> + 0x87, 6, /* DW_CFA_offset, r7, -24 */
> + 0x86, 7, /* DW_CFA_offset, r6, -28 */
> + 0x85, 8, /* DW_CFA_offset, r5, -32 */
> + 0x84, 9, /* DW_CFA_offset, r4, -36 */
> + }
> +};
> +
> +void tcg_register_jit(void *buf, size_t buf_size)
> +{
> + /* We're expecting a 2 byte uleb128 encoded value. */
> + assert(FRAME_SIZE >> 14 == 0);
> +
> + debug_frame.fde.func_start = (tcg_target_long) buf;
> + debug_frame.fde.func_len = buf_size;
> +
> + tcg_register_jit_int(buf, buf_size, &debug_frame, sizeof(debug_frame));
> +}
