diff options
Diffstat (limited to 'include/common/aarch64/asm_macros.S')
| -rw-r--r-- | include/common/aarch64/asm_macros.S | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/include/common/aarch64/asm_macros.S b/include/common/aarch64/asm_macros.S index cc8f4243..88e8d9c6 100644 --- a/include/common/aarch64/asm_macros.S +++ b/include/common/aarch64/asm_macros.S @@ -178,4 +178,26 @@ .endif .endm + /* + * Macro to mark instances where we're jumping to a function and don't + * expect a return. To provide the function being jumped to with + * additional information, we use 'bl' instruction to jump rather than + * 'b'. + * + * Debuggers infer the location of a call from where LR points to, which + * is usually the instruction after 'bl'. If this macro expansion + * happens to be the last location in a function, that'll cause the LR + * to point a location beyond the function, thereby misleading debugger + * back trace. We therefore insert a 'nop' after the function call for + * debug builds, unless 'skip_nop' parameter is non-zero. + */ + .macro no_ret _func:req, skip_nop=0 + bl \_func +#if DEBUG + .ifeq \skip_nop + nop + .endif +#endif + .endm + #endif /* __ASM_MACROS_S__ */ |