RISC-V: alternatives: Support patching multiple insns in assembly
authorAndrew Jones <ajones@ventanamicro.com>
Fri, 24 Feb 2023 16:26:24 +0000 (17:26 +0100)
committerPalmer Dabbelt <palmer@rivosinc.com>
Wed, 15 Mar 2023 04:26:01 +0000 (21:26 -0700)
As pointed out in commit d374a16539b1 ("RISC-V: fix compile error
from deduplicated __ALTERNATIVE_CFG_2"), we need quotes around
parameters passed to macros within macros to avoid spaces being
interpreted as separators. ALT_NEW_CONTENT was trying to handle
this by defining new_c has a vararg, but this isn't sufficient
for calling ALTERNATIVE() from assembly with multiple instructions
in the new/old sequences. Remove the vararg "hack" and use quotes.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230224162631.405473-2-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
arch/riscv/include/asm/alternative-macros.h

index 993a44a8fdacfbcf4a08ccc0f833b21f93925d49..b8c55fb3ab2c07cab4c26875903c3eef76d08853 100644 (file)
@@ -14,7 +14,7 @@
        .4byte \patch_id
 .endm
 
-.macro ALT_NEW_CONTENT vendor_id, patch_id, enable = 1, new_c : vararg
+.macro ALT_NEW_CONTENT vendor_id, patch_id, enable = 1, new_c
        .if \enable
        .pushsection .alternative, "a"
        ALT_ENTRY 886b, 888f, \vendor_id, \patch_id, 889f - 888f
        \old_c
        .option pop
 887 :
-       ALT_NEW_CONTENT \vendor_id, \patch_id, \enable, \new_c
+       ALT_NEW_CONTENT \vendor_id, \patch_id, \enable, "\new_c"
 .endm
 
 .macro ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, patch_id_1, enable_1,    \
                                new_c_2, vendor_id_2, patch_id_2, enable_2
        ALTERNATIVE_CFG "\old_c", "\new_c_1", \vendor_id_1, \patch_id_1, \enable_1
-       ALT_NEW_CONTENT \vendor_id_2, \patch_id_2, \enable_2, \new_c_2
+       ALT_NEW_CONTENT \vendor_id_2, \patch_id_2, \enable_2, "\new_c_2"
 .endm
 
 #define __ALTERNATIVE_CFG(...)         ALTERNATIVE_CFG __VA_ARGS__