Displaying 4 results from an estimated 4 matches for "log2_32_ceil".
2009 Oct 13
1
[LLVMdev] 65bit integer math
...he big hack we put in, which is just the code that used to be there
in 2.3:
// We need at least W + T bits for the multiplication step
// FIXME: A temporary hack; we round up the bitwidths
// to the nearest power of 2 to be nice to the code generator.
unsigned CalculationBits = 1U << Log2_32_Ceil(W + T);
// Cray: Truncate to 64 bits. It's what we did with LLVM 2.3 and
// while it can create miscompilations in some cases if the
// computation happens to overflow, it's no worse than what we did
// before.
if (CalculationBits > 64) {
//return new SCEVCouldNotCompute(...
2009 Oct 13
0
[LLVMdev] 65bit integer math
On Mon, Oct 12, 2009 at 6:15 PM, Villmow, Micah <Micah.Villmow at amd.com> wrote:
> I have a test case(attached as fc_long.ll) that when run through the
> optimizer produces 65bit integer math(fc_long-opt.ll).
>
>
>
> Now I understand that llvm can have any length integer, but I consider
> turning a 64bit mul into multiple 65 bit instructions to be a ‘bad’
>
2009 Oct 13
4
[LLVMdev] 65bit integer math
I have a test case(attached as fc_long.ll) that when run through the
optimizer produces 65bit integer math(fc_long-opt.ll).
Now I understand that llvm can have any length integer, but I consider
turning a 64bit mul into multiple 65 bit instructions to be a 'bad'
optimization. This eventually expands to a 128bit multiply
call(__multi3) which I have absolutely no interest in supporting.
2017 Apr 04
3
RFC: Adding a string table to the bitcode format
On Tue, Apr 4, 2017 at 12:36 PM, Duncan P. N. Exon Smith <
dexonsmith at apple.com> wrote:
>
> On 2017-Apr-04, at 12:12, Peter Collingbourne <peter at pcc.me.uk> wrote:
>
> On Mon, Apr 3, 2017 at 8:13 PM, Mehdi Amini <mehdi.amini at apple.com> wrote:
>
>>
>> On Apr 3, 2017, at 7:08 PM, Peter Collingbourne <peter at pcc.me.uk> wrote:
>>