Re: [PATCH 7/7] crypto, x86, LLVM: aesni - fix token pasting

[Matthias Kaehlcke]

El Thu, Mar 16, 2017 at 05:15:20PM -0700 Michael Davidson ha dit:

> aes_ctrby8_avx-x86_64.S uses the C preprocessor for token pasting
> of character sequences that are not valid preprocessor tokens.
> While this is allowed when preprocessing assembler files it exposes
> an incompatibilty between the clang and gcc preprocessors where
> clang does not strip leading white space from macro parameters,
> leading to the CONCAT(%xmm, i) macro expansion on line 96 resulting
> in a token with a space character embedded in it.
> 
> While this could be fixed by deleting the offending space character,
> the assembler is perfectly capable of handling the token pasting
> correctly for itself so it seems preferable to let it do so and to
> get rid or the CONCAT(), DDQ() and XMM() preprocessor macros.
> 
> Signed-off-by: Michael Davidson 
> ---
>  arch/x86/crypto/aes_ctrby8_avx-x86_64.S | 7 ++-
>  1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S 
> b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
> index a916c4a61165..5f6a5af9c489 100644
> --- a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
> +++ b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
> @@ -65,7 +65,6 @@
>  #include 
>  #include 
>  
> -#define CONCAT(a,b)  a##b
>  #define VMOVDQ   vmovdqu
>  
>  #define xdata0   %xmm0
> @@ -92,8 +91,6 @@
>  #define num_bytes%r8
>  
>  #define tmp  %r10
> -#define  DDQ(i)  CONCAT(ddq_add_,i)
> -#define  XMM(i)  CONCAT(%xmm, i)
>  #define  DDQ_DATA0
>  #define  XDATA   1
>  #define KEY_128  1
> @@ -131,12 +128,12 @@ ddq_add_8:
>  /* generate a unique variable for ddq_add_x */
>  
>  .macro setddq n
> - var_ddq_add = DDQ(\n)
> + var_ddq_add = ddq_add_\n
>  .endm
>  
>  /* generate a unique variable for xmm register */
>  .macro setxdata n
> - var_xdata = XMM(\n)
> + var_xdata = %xmm\n
>  .endm
>  
>  /* club the numeric 'id' to the symbol 'name' */

Any feedback on this patch?

Thanks

Matthias

[PATCH 7/7] crypto, x86, LLVM: aesni - fix token pasting

[Michael Davidson]

aes_ctrby8_avx-x86_64.S uses the C preprocessor for token pasting
of character sequences that are not valid preprocessor tokens.
While this is allowed when preprocessing assembler files it exposes
an incompatibilty between the clang and gcc preprocessors where
clang does not strip leading white space from macro parameters,
leading to the CONCAT(%xmm, i) macro expansion on line 96 resulting
in a token with a space character embedded in it.

While this could be fixed by deleting the offending space character,
the assembler is perfectly capable of handling the token pasting
correctly for itself so it seems preferable to let it do so and to
get rid or the CONCAT(), DDQ() and XMM() preprocessor macros.

Signed-off-by: Michael Davidson 
---
 arch/x86/crypto/aes_ctrby8_avx-x86_64.S | 7 ++-
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S 
b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
index a916c4a61165..5f6a5af9c489 100644
--- a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
+++ b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
@@ -65,7 +65,6 @@
 #include 
 #include 
 
-#define CONCAT(a,b)a##b
 #define VMOVDQ vmovdqu
 
 #define xdata0 %xmm0
@@ -92,8 +91,6 @@
 #define num_bytes  %r8
 
 #define tmp%r10
-#defineDDQ(i)  CONCAT(ddq_add_,i)
-#defineXMM(i)  CONCAT(%xmm, i)
 #defineDDQ_DATA0
 #defineXDATA   1
 #define KEY_1281
@@ -131,12 +128,12 @@ ddq_add_8:
 /* generate a unique variable for ddq_add_x */
 
 .macro setddq n
-   var_ddq_add = DDQ(\n)
+   var_ddq_add = ddq_add_\n
 .endm
 
 /* generate a unique variable for xmm register */
 .macro setxdata n
-   var_xdata = XMM(\n)
+   var_xdata = %xmm\n
 .endm
 
 /* club the numeric 'id' to the symbol 'name' */
-- 
2.12.0.367.g23dc2f6d3c-goog