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common/ndsabi/macros.inc

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+// SPDX-License-Identifier: Zlib
+// SPDX-FileNotice: Modified from the original version by the BlocksDS project.
+//
+// Copyright (C) 2021-2023 agbabi contributors
+//
+// ARM assembly support macros
+
+@ Shift and test upper two bits, clobbering \reg
+@ Use mi for first bit, cs for second bit
+.macro joaobapt_test_lsl reg shift = #0
+    movs    \reg, \reg, lsl \shift
+.endm
+
+@ Test lowest two bits, clobbering \reg
+@ Use mi for low bit, cs for high bit
+.macro joaobapt_test reg
+    joaobapt_test_lsl \reg, #31
+.endm
+
+@ Test lowest two bits of \src, result stored in \dst
+@ Use mi for low bit, cs for high bit
+.macro joaobapt_test_into dst, src
+    movs    \dst, \src, lsl #31
+.endm
+
+@ Branches depending on lowest two bits, clobbering \reg
+@ b_mi = low bit case, b_cs = high bit case
+.macro joaobapt_switch reg, b_mi, b_cs
+    joaobapt_test \reg
+    bmi     \b_mi
+    bcs     \b_cs
+.endm
+
+@ Branches depending on alignment of \a and \b, clobbering \scratch
+@ b_byte = off-by-byte case, b_half = off-by-half case
+.macro align_switch a, b, scratch, b_byte, b_half
+    eor     \scratch, \a, \b
+    joaobapt_switch \scratch, \b_byte, \b_half
+.endm