[PATCH 5.7] x86/crypto: aesni: Fix build with LLVM_IAS=1

[Sedat Dilek]

When building with LLVM_IAS=1 means using Clang's Integrated Assembly (IAS)
from LLVM/Clang >= v10.0.1-rc1+ instead of GNU/as from GNU/binutils
I see the following breakage in Debian/testing AMD64:

<instantiation>:15:74: error: too many positional arguments
 PRECOMPUTE 8*3+8(%rsp), %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7,
                                                                         ^
 arch/x86/crypto/aesni-intel_asm.S:1598:2: note: while in macro instantiation
 GCM_INIT %r9, 8*3 +8(%rsp), 8*3 +16(%rsp), 8*3 +24(%rsp)
 ^
<instantiation>:47:2: error: unknown use of instruction mnemonic without a size suffix
 GHASH_4_ENCRYPT_4_PARALLEL_dec %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, %xmm0, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7, %xmm8, enc
 ^
arch/x86/crypto/aesni-intel_asm.S:1599:2: note: while in macro instantiation
 GCM_ENC_DEC dec
 ^
<instantiation>:15:74: error: too many positional arguments
 PRECOMPUTE 8*3+8(%rsp), %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7,
                                                                         ^
arch/x86/crypto/aesni-intel_asm.S:1686:2: note: while in macro instantiation
 GCM_INIT %r9, 8*3 +8(%rsp), 8*3 +16(%rsp), 8*3 +24(%rsp)
 ^
<instantiation>:47:2: error: unknown use of instruction mnemonic without a size suffix
 GHASH_4_ENCRYPT_4_PARALLEL_enc %xmm9, %xmm10, %xmm11, %xmm12, %xmm13, %xmm14, %xmm0, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7, %xmm8, enc
 ^
arch/x86/crypto/aesni-intel_asm.S:1687:2: note: while in macro instantiation
 GCM_ENC_DEC enc
 
Craig Topper suggested me in ClangBuiltLinux issue #1050:

> I think the "too many positional arguments" is because the parser isn't able
> to handle the trailing commas.
> 
> The "unknown use of instruction mnemonic" is because the macro was named
> GHASH_4_ENCRYPT_4_PARALLEL_DEC but its being instantiated with 
> GHASH_4_ENCRYPT_4_PARALLEL_dec I guess gas ignores case on the
> macro instantiation, but llvm doesn't.

First, I removed the trailing comma in the PRECOMPUTE line.

Second, I substituted:
1. GCM_ENC_DEC dec -> GCM_ENC_DEC DEC
2. GCM_ENC_DEC enc -> GCM_ENC_DEC ENC

With these changes I was able to build with LLVM_IAS=1 and boot on bare metal.

As llvm-toolchain I used v10.0.1-rc1+ and v11.0.0-git pre-releases:
1. release/10.x Git: 2dc664d578f0e9c8ea5975eed745e322fa77bffe
2.       master Git: 8da5b9083691b557f50f72ab099598bb291aec5f (default)

Just for the sake of completeness:
1. CONFIG_DEBUG_INFO_DWARF4=y
2. OBJDUMP=llvm-objdump (passed to my make-line)

Please have a look into "llvm.rst" kernel-doc for further informations and
how to pass LLVM kbuild-options to your make-line.

I confirmed that this works with Linux-kernel v5.7.3 and v5.7.5 final.

NOTE: This patch is on top of Linux v5.7 final.

Thanks to Craig and the folks from the ClangBuiltLinux project.

Cc: Craig Topper <craig.topper@xxxxxxxxx>
Cc: Craig Topper <craig.topper@xxxxxxxxx>
Cc: Nick Desaulniers ndesaulniers@xxxxxxxxxx
Cc: "ClangBuiltLinux" <clang-built-linux@xxxxxxxxxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/1050
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/kbuild/llvm.rst

---
 arch/x86/crypto/aesni-intel_asm.S | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S
index cad6e1bfa7d5..983eb2eec51a 100644
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -266,7 +266,7 @@ ALL_F:      .octa 0xffffffffffffffffffffffffffffffff
 	PSHUFB_XMM %xmm2, %xmm0
 	movdqu %xmm0, CurCount(%arg2) # ctx_data.current_counter = iv
 
-	PRECOMPUTE \SUBKEY, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7,
+	PRECOMPUTE \SUBKEY, %xmm1, %xmm2, %xmm3, %xmm4, %xmm5, %xmm6, %xmm7
 	movdqu HashKey(%arg2), %xmm13
 
 	CALC_AAD_HASH %xmm13, \AAD, \AADLEN, %xmm0, %xmm1, %xmm2, %xmm3, \
@@ -1596,7 +1596,7 @@ SYM_FUNC_START(aesni_gcm_dec)
 	FUNC_SAVE
 
 	GCM_INIT %arg6, arg7, arg8, arg9
-	GCM_ENC_DEC dec
+	GCM_ENC_DEC DEC
 	GCM_COMPLETE arg10, arg11
 	FUNC_RESTORE
 	ret
@@ -1684,7 +1684,7 @@ SYM_FUNC_START(aesni_gcm_enc)
 	FUNC_SAVE
 
 	GCM_INIT %arg6, arg7, arg8, arg9
-	GCM_ENC_DEC enc
+	GCM_ENC_DEC ENC
 
 	GCM_COMPLETE arg10, arg11
 	FUNC_RESTORE
@@ -1719,7 +1719,7 @@ SYM_FUNC_END(aesni_gcm_init)
 */
 SYM_FUNC_START(aesni_gcm_enc_update)
 	FUNC_SAVE
-	GCM_ENC_DEC enc
+	GCM_ENC_DEC ENC
 	FUNC_RESTORE
 	ret
 SYM_FUNC_END(aesni_gcm_enc_update)
@@ -1734,7 +1734,7 @@ SYM_FUNC_END(aesni_gcm_enc_update)
 */
 SYM_FUNC_START(aesni_gcm_dec_update)
 	FUNC_SAVE
-	GCM_ENC_DEC dec
+	GCM_ENC_DEC DEC
 	FUNC_RESTORE
 	ret
 SYM_FUNC_END(aesni_gcm_dec_update)
-- 
2.27.0