Commit Graph

3 Commits

Author SHA1 Message Date
Sjoerd Meijer fc448cfd25 [ARM][NFC] codegen tests cleanup: remove dangling check prefixes
I am working on making FileCheck stricter (in D54769 and D53710) so that it
issues diagnostics when there's something wrong with tests.

This is a cleanup for dangling prefixes in the ARM codegen tests, e.g.:

--check-prefixes=A,B

where A occurs in the check file, but B doesn't. This can be innocent if A does
all the required checking, but can also be a bug in that test if it results in
the test actually not checking anything (if A for example only checks a common
label). Test CodeGen/ARM/smml.ll is such an example.

Differential Revision: https://reviews.llvm.org/D54842

llvm-svn: 347487
2018-11-23 10:08:39 +00:00
Sam Parker e7c42dd7e2 [ARM] Remove trunc sinks in ARM CGP
Truncs are treated as sources if their produce a value of the same
type as the one we currently trying to promote. Truncs used to be
considered as a sink if their operand was the same value type.
    
We now allow smaller types in the search, so we should search through
truncs that produce a smaller value. These truncs can then be
converted to an AND mask.
    
This leaves sinks as being:
  - points where the value in the register is being observed, such as
    an icmp, switch or store.
  - points where value types have to match, such as calls and returns.
  - zext are included to ease the transformation and are generally
    removed later on.
    
During this change, it also became apart from truncating sinks was
broken: if a sink used a source, its type information had already
been lost by the time the truncation happens. So I've changed the
method of caching the type information.

Differential Revision: https://reviews.llvm.org/D54515

llvm-svn: 347191
2018-11-19 11:34:40 +00:00
Sam Parker 84a2f8b364 [ARM][CGP] Negative constant operand handling
While mutating instructions, we sign extended negative constant
operands for binary operators that can safely overflow. This was to
allow instructions, such as add nuw i8 %a, -2, to still be able to
perform a subtraction. However, the code to handle constants doesn't
take into consideration that instructions, such as sub nuw i8 -2, %a,
require the i8 -2 to be converted into i32 254.

This is a relatively simple fix, but I've taken the time to
reorganise the code a bit - mainly that instructions that can be
promoted are cached and splitting up the Mutate function.

Differential Revision: https://reviews.llvm.org/D53972

llvm-svn: 345840
2018-11-01 15:23:42 +00:00