Armv8.1-M: Add clean x4 Keccak code and SLOTHY Makefile

.github/workflows/ci_ec2_reusable.yml

@@ -207,7 +207,7 @@ jobs:
           nix-cache: true
           nix-shell: slothy
           script: |
-            autogen --slothy
+            autogen --slothy aarch64
             tests all --opt opt
             # Force testing of SLOTHY-optimized Keccak variants
             # We can't run the examples here because some of them also specify the backend

dev/fips202/armv81m/src/Makefile

@@ -0,0 +1,47 @@
+# Copyright (c) The mlkem-native project authors
+# SPDX-License-Identifier: Apache-2.0 OR ISC OR MIT
+
+.PHONY: all purge
+.DEFAULT_GOAL := all
+
+# ISA to optimize for
+TARGET_ISA=Arm_v81M
+
+# MicroArch target to optimize for
+TARGET_MICROARCH=Arm_Cortex_M55
+
+keccak_f1600_x4_mve.S: ../../armv81m_symbolic/keccak_f1600_x4_mve_clean.S
+	$(eval TMP := $(shell mktemp))
+	slothy-cli $(TARGET_ISA) $(TARGET_MICROARCH) $< -o $(TMP) \
+		-s keccak_f1600_x4_mve_asm_roundstart \
+		-e keccak_f1600_x4_mve_asm_roundend_pre \
+		-c unsafe_address_offset_fixup=False \
+		-c inputs_are_outputs=True \
+		-c constraints.functional_only=True \
+		-c constraints.allow_reordering=True \
+		-c constraints.max_displacement=0.1
+	slothy-cli $(TARGET_ISA) $(TARGET_MICROARCH) $(TMP) -o $@ \
+		-s keccak_f1600_x4_mve_asm_roundstart \
+		-e keccak_f1600_x4_mve_asm_roundend_pre \
+		-c constraints.functional_only=False \
+		-c constraints.allow_reordering=True \
+		-c variable_size=True \
+        -c inputs_are_outputs=True \
+		-c constraints.stalls_first_attempt=64 \
+		-c constraints.max_displacement=1.0 \
+		-c constraints.stalls_maximum_attempt=4096 \
+        -c unsafe_address_offset_fixup=False \
+		-c split_heuristic=True \
+		-c split_heuristic_stepsize=0.05 \
+		-c split_heuristic_factor=26 \
+		-c split_heuristic_repeat=2 \
+		-c split_heuristic_estimate_performance=False \
+		-c split_heuristic_optimize_seam=2
+	rm -f $(TMP)
+
+ALL=keccak_f1600_x4_mve.S
+
+all: $(ALL)
+
+purge:
+	rm -rf $(ALL)