Rework gcm128 implementation selection for amd64/i386.

Provide gcm128_amd64.c and gcm128_i386.c, which contain the appropriate
gcm128 initialisation and CPU feature tests for the respective platform.
This allows for all of the #define spagetti to be removed from gcm128.c
and removes one of the two remaining consumers of crypto_cpu_caps_ia32().

ok tb@

2 files changed, 8 insertions, 2 deletions

diff --git a/src/lib/libcrypto/arch/amd64/Makefile.inc b/src/lib/libcrypto/arch/amd64/Makefile.inc
index 5ecf8f1390..649c507189 100644
--- a/src/lib/libcrypto/arch/amd64/Makefile.inc
+++ b/src/lib/libcrypto/arch/amd64/Makefile.inc
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile.inc,v 1.40 2025/06/15 15:11:50 jsing Exp $
+# $OpenBSD: Makefile.inc,v 1.41 2025/06/28 12:39:10 jsing Exp $
 
 # amd64-specific libcrypto build rules
 
@@ -38,11 +38,15 @@ SRCS += word_clz.S
 # md5
 CFLAGS+= -DMD5_ASM
 SRCS+= md5_amd64_generic.S
+
 # modes
 CFLAGS+= -DGHASH_ASM
 SSLASM+= modes ghash-x86_64
+SRCS += gcm128_amd64.c
+
 # rc4
 SSLASM+= rc4 rc4-x86_64
+
 # ripemd
 # sha
 SRCS+= sha1_amd64.c
diff --git a/src/lib/libcrypto/arch/amd64/crypto_arch.h b/src/lib/libcrypto/arch/amd64/crypto_arch.h
index 213a5d903e..9f292cc530 100644
--- a/src/lib/libcrypto/arch/amd64/crypto_arch.h
+++ b/src/lib/libcrypto/arch/amd64/crypto_arch.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: crypto_arch.h,v 1.8 2025/06/28 12:20:39 jsing Exp $ */
+/*      $OpenBSD: crypto_arch.h,v 1.9 2025/06/28 12:39:10 jsing Exp $ */
 /*
  * Copyright (c) 2024 Joel Sing <jsing@openbsd.org>
  *
@@ -40,6 +40,8 @@ extern uint64_t crypto_cpu_caps_amd64;
 #define HAVE_AES_CBC_ENCRYPT_INTERNAL
 #define HAVE_AES_CTR32_ENCRYPT_INTERNAL
 
+#define HAVE_GCM128_INIT
+
 #define HAVE_RC4_INTERNAL
 #define HAVE_RC4_SET_KEY_INTERNAL