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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/h8300/lib/mulsi3.S | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/h8300/lib/mulsi3.S')
-rw-r--r-- | arch/h8300/lib/mulsi3.S | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/arch/h8300/lib/mulsi3.S b/arch/h8300/lib/mulsi3.S new file mode 100644 index 000000000..5a062fd29 --- /dev/null +++ b/arch/h8300/lib/mulsi3.S @@ -0,0 +1,39 @@ +; SPDX-License-Identifier: GPL-2.0 +; +; mulsi3 for H8/300H - based on Renesas SH implementation +; +; by Toshiyasu Morita +; +; Old code: +; +; 16b * 16b = 372 states (worst case) +; 32b * 32b = 724 states (worst case) +; +; New code: +; +; 16b * 16b = 48 states +; 16b * 32b = 72 states +; 32b * 32b = 92 states +; + + .global __mulsi3 +__mulsi3: + mov.w r1,r2 ; ( 2 states) b * d + mulxu r0,er2 ; (22 states) + + mov.w e0,r3 ; ( 2 states) a * d + beq L_skip1 ; ( 4 states) + mulxu r1,er3 ; (22 states) + add.w r3,e2 ; ( 2 states) + +L_skip1: + mov.w e1,r3 ; ( 2 states) c * b + beq L_skip2 ; ( 4 states) + mulxu r0,er3 ; (22 states) + add.w r3,e2 ; ( 2 states) + +L_skip2: + mov.l er2,er0 ; ( 2 states) + rts ; (10 states) + + .end |