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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 /common/Values.v | |
parent | a44893028eb1dd434c68001234ad56d030205a8e (diff) | |
download | compcert-d2af79a77ed2936ff0ed90cadf8e48637d774d4c.tar.gz compcert-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 'common/Values.v')
-rw-r--r-- | common/Values.v | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/common/Values.v b/common/Values.v index 88506bab..cfabb7a5 100644 --- a/common/Values.v +++ b/common/Values.v @@ -622,6 +622,18 @@ Definition mull' (v1 v2: val): val := | _, _ => Vundef end. +Definition mullhs (v1 v2: val): val := + match v1, v2 with + | Vlong n1, Vlong n2 => Vlong(Int64.mulhs n1 n2) + | _, _ => Vundef + end. + +Definition mullhu (v1 v2: val): val := + match v1, v2 with + | Vlong n1, Vlong n2 => Vlong(Int64.mulhu n1 n2) + | _, _ => Vundef + end. + Definition divls (v1 v2: val): option val := match v1, v2 with | Vlong n1, Vlong n2 => |