[PATCH] lib/crypto: arm64/sha3: Use assembler for sha3 instructions

[PATCH] lib/crypto: arm64/sha3: Use assembler for sha3 instructions

[Eric Biggers]

All supported assemblers (binutils 2.30 and later, and clang 17.0.1 and
later) support the sha3 instructions now.

Therefore, drop the use of '.inst' in sha3-ce-core.S and just have the
assembler generate the instructions.

This requires adding '.arch armv8.2-a+sha3'.  I also tried just
'.arch_extension sha3', but that doesn't work with binutils 2.40 and
earlier because they consider sha3 to depend on armv8.2-a or later (and
this file isn't built with -march=armv8.2-a or later).  This was fixed
in binutils 2.41 commit 205e4380c800, but the kernel currently supports
binutils 2.30 and later.

Also prefix the immediate operands to 'xar' with '#', now that they no
longer need to be plain numbers to generate an .inst.  This isn't
required, but it follows the standard convention for immediates in arm64
assembly, including elsewhere in the same file.

No change in the resulting .text section with either binutils or clang.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---

This patch is intended to be taken through libcrypto-next

 lib/crypto/arm64/sha3-ce-core.S | 73 ++++++++++++---------------------
 1 file changed, 26 insertions(+), 47 deletions(-)

diff --git a/lib/crypto/arm64/sha3-ce-core.S b/lib/crypto/arm64/sha3-ce-core.S
index b8ab01987ae07..02f225fd86ced 100644
--- a/lib/crypto/arm64/sha3-ce-core.S
+++ b/lib/crypto/arm64/sha3-ce-core.S
@@ -12,29 +12,8 @@
 #include <linux/linkage.h>
 #include <asm/assembler.h>
 
-	.irp	b,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31
-	.set	.Lv\b\().2d, \b
-	.set	.Lv\b\().16b, \b
-	.endr
-
-	/*
-	 * ARMv8.2 Crypto Extensions instructions
-	 */
-	.macro	eor3, rd, rn, rm, ra
-	.inst	0xce000000 | .L\rd | (.L\rn << 5) | (.L\ra << 10) | (.L\rm << 16)
-	.endm
-
-	.macro	rax1, rd, rn, rm
-	.inst	0xce608c00 | .L\rd | (.L\rn << 5) | (.L\rm << 16)
-	.endm
-
-	.macro	bcax, rd, rn, rm, ra
-	.inst	0xce200000 | .L\rd | (.L\rn << 5) | (.L\ra << 10) | (.L\rm << 16)
-	.endm
-
-	.macro	xar, rd, rn, rm, imm6
-	.inst	0xce800000 | .L\rd | (.L\rn << 5) | ((\imm6) << 10) | (.L\rm << 16)
-	.endm
+	/* In binutils 2.40 and earlier, sha3 depends on armv8.2-a or later. */
+	.arch	armv8.2-a+sha3
 
 	/*
 	 * void sha3_ce_transform(struct sha3_state *state, const u8 *data,
@@ -125,30 +104,30 @@ SYM_FUNC_START(sha3_ce_transform)
 	rax1	v27.2d, v27.2d, v29.2d	// bc[3]
 
 	eor	 v0.16b,  v0.16b, v30.16b
-	xar	 v29.2d,   v1.2d,  v25.2d, (64 - 1)
-	xar	  v1.2d,   v6.2d,  v25.2d, (64 - 44)
-	xar	  v6.2d,   v9.2d,  v28.2d, (64 - 20)
-	xar	  v9.2d,  v22.2d,  v26.2d, (64 - 61)
-	xar	 v22.2d,  v14.2d,  v28.2d, (64 - 39)
-	xar	 v14.2d,  v20.2d,  v30.2d, (64 - 18)
-	xar	 v31.2d,   v2.2d,  v26.2d, (64 - 62)
-	xar	  v2.2d,  v12.2d,  v26.2d, (64 - 43)
-	xar	 v12.2d,  v13.2d,  v27.2d, (64 - 25)
-	xar	 v13.2d,  v19.2d,  v28.2d, (64 - 8)
-	xar	 v19.2d,  v23.2d,  v27.2d, (64 - 56)
-	xar	 v23.2d,  v15.2d,  v30.2d, (64 - 41)
-	xar	 v15.2d,   v4.2d,  v28.2d, (64 - 27)
-	xar	 v28.2d,  v24.2d,  v28.2d, (64 - 14)
-	xar	 v24.2d,  v21.2d,  v25.2d, (64 - 2)
-	xar	  v8.2d,   v8.2d,  v27.2d, (64 - 55)
-	xar	  v4.2d,  v16.2d,  v25.2d, (64 - 45)
-	xar	 v16.2d,   v5.2d,  v30.2d, (64 - 36)
-	xar	  v5.2d,   v3.2d,  v27.2d, (64 - 28)
-	xar	 v27.2d,  v18.2d,  v27.2d, (64 - 21)
-	xar	  v3.2d,  v17.2d,  v26.2d, (64 - 15)
-	xar	 v25.2d,  v11.2d,  v25.2d, (64 - 10)
-	xar	 v26.2d,   v7.2d,  v26.2d, (64 - 6)
-	xar	 v30.2d,  v10.2d,  v30.2d, (64 - 3)
+	xar	 v29.2d,   v1.2d,  v25.2d, #64 - 1
+	xar	  v1.2d,   v6.2d,  v25.2d, #64 - 44
+	xar	  v6.2d,   v9.2d,  v28.2d, #64 - 20
+	xar	  v9.2d,  v22.2d,  v26.2d, #64 - 61
+	xar	 v22.2d,  v14.2d,  v28.2d, #64 - 39
+	xar	 v14.2d,  v20.2d,  v30.2d, #64 - 18
+	xar	 v31.2d,   v2.2d,  v26.2d, #64 - 62
+	xar	  v2.2d,  v12.2d,  v26.2d, #64 - 43
+	xar	 v12.2d,  v13.2d,  v27.2d, #64 - 25
+	xar	 v13.2d,  v19.2d,  v28.2d, #64 - 8
+	xar	 v19.2d,  v23.2d,  v27.2d, #64 - 56
+	xar	 v23.2d,  v15.2d,  v30.2d, #64 - 41
+	xar	 v15.2d,   v4.2d,  v28.2d, #64 - 27
+	xar	 v28.2d,  v24.2d,  v28.2d, #64 - 14
+	xar	 v24.2d,  v21.2d,  v25.2d, #64 - 2
+	xar	  v8.2d,   v8.2d,  v27.2d, #64 - 55
+	xar	  v4.2d,  v16.2d,  v25.2d, #64 - 45
+	xar	 v16.2d,   v5.2d,  v30.2d, #64 - 36
+	xar	  v5.2d,   v3.2d,  v27.2d, #64 - 28
+	xar	 v27.2d,  v18.2d,  v27.2d, #64 - 21
+	xar	  v3.2d,  v17.2d,  v26.2d, #64 - 15
+	xar	 v25.2d,  v11.2d,  v25.2d, #64 - 10
+	xar	 v26.2d,   v7.2d,  v26.2d, #64 - 6
+	xar	 v30.2d,  v10.2d,  v30.2d, #64 - 3
 
 	bcax	v20.16b, v31.16b, v22.16b,  v8.16b
 	bcax	v21.16b,  v8.16b, v23.16b, v22.16b

base-commit: 7475ea8b58616b33c04afb976cf0fbaad9dd63fb
-- 
2.56.1