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author | Xavier Leroy <xavier.leroy@inria.fr> | 2016-10-04 15:52:16 +0200 |
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committer | Xavier Leroy <xavier.leroy@inria.fr> | 2016-10-04 15:52:16 +0200 |
commit | d2af79a77ed2936ff0ed90cadf8e48637d774d4c (patch) | |
tree | 09300943e12a98ae80598c79d455b31725271ead /backend/Selection.v | |
parent | a44893028eb1dd434c68001234ad56d030205a8e (diff) | |
download | compcert-kvx-d2af79a77ed2936ff0ed90cadf8e48637d774d4c.tar.gz compcert-kvx-d2af79a77ed2936ff0ed90cadf8e48637d774d4c.zip |
Turn 64-bit integer division and modulus by constants into multiply-high
This trick was already implemented for 32-bit integer division and modulus. Here we extend it to the 64-bit case.
For 32-bit target processors, the runtime library must implement 64-bit multiply-high (signed and unsigned). Tentative implementations are provided for IA32 and PowerPC, but need testing.
Diffstat (limited to 'backend/Selection.v')
-rw-r--r-- | backend/Selection.v | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/backend/Selection.v b/backend/Selection.v index 5cb5d119..abda1d95 100644 --- a/backend/Selection.v +++ b/backend/Selection.v @@ -389,10 +389,13 @@ Definition get_helpers (defmap: PTree.t globdef) : res helper_functions := do i64_shl <- lookup_helper globs "__i64_shl" sig_li_l ; do i64_shr <- lookup_helper globs "__i64_shr" sig_li_l ; do i64_sar <- lookup_helper globs "__i64_sar" sig_li_l ; + do i64_umulh <- lookup_helper globs "__i64_umulh" sig_ll_l ; + do i64_smulh <- lookup_helper globs "__i64_smulh" sig_ll_l ; OK (mk_helper_functions i64_dtos i64_dtou i64_stod i64_utod i64_stof i64_utof i64_sdiv i64_udiv i64_smod i64_umod - i64_shl i64_shr i64_sar). + i64_shl i64_shr i64_sar + i64_umulh i64_smulh). (** Conversion of programs. *) |