llvm-project

Commit Graph

Author	SHA1	Message	Date
Jinsong Ji	b7b3d866a4	[PowerPC][NFC] Fix typos in triples Found by bzEq (Kai Luo). llvm-svn: 360643	2019-05-14 03:11:24 +00:00
Nemanja Ivanovic	5cf902ccd4	[PowerPC] Do not use vectors to codegen bswap with Altivec turned off We have efficient codegen on P9 for lowering bswap that involves moving the value into a vector reg and moving it back. However, the check under which we custom lowered it did not adequately reflect the actual requirements. It required only that the subtarget be an implementation of ISA 3.0 since all compliant implementations have to provide the vector instructions. However, the kernel builds have a valid use case for -mno-altivec -mcpu=pwr9 (i.e. don't emit vector code, don't have to save vector regs for context switch). So we should require the correct features for this lowering. Fixes https://bugs.llvm.org/show_bug.cgi?id=39334 llvm-svn: 347376	2018-11-21 02:53:50 +00:00
Guozhi Wei	e3b8d9a312	[PPC] Use xxbrd to speed up bswap64 Power doesn't have bswap instructions, so llvm generates following code sequence for bswap64. rotldi 5, 3, 16 rotldi 4, 3, 8 rotldi 9, 3, 24 rotldi 10, 3, 32 rotldi 11, 3, 48 rotldi 12, 3, 56 rldimi 4, 5, 8, 48 rldimi 4, 9, 16, 40 rldimi 4, 10, 24, 32 rldimi 4, 11, 40, 16 rldimi 4, 12, 48, 8 rldimi 4, 3, 56, 0 But Power9 has vector bswap instructions, they can also be used to speed up scalar bswap intrinsic. With this patch, bswap64 can be translated to: mtvsrdd 34, 3, 3 xxbrd 34, 34 mfvsrld 3, 34 Differential Revision: https://reviews.llvm.org/D39510 llvm-svn: 317499	2017-11-06 19:09:38 +00:00

Author

SHA1

Message

Date

Jinsong Ji

b7b3d866a4

[PowerPC][NFC] Fix typos in triples

Found by bzEq (Kai Luo).

llvm-svn: 360643

2019-05-14 03:11:24 +00:00

Nemanja Ivanovic

5cf902ccd4

[PowerPC] Do not use vectors to codegen bswap with Altivec turned off

We have efficient codegen on P9 for lowering bswap that involves moving
the value into a vector reg and moving it back. However, the check under
which we custom lowered it did not adequately reflect the actual requirements.
It required only that the subtarget be an implementation of ISA 3.0 since all
compliant implementations have to provide the vector instructions.
However, the kernel builds have a valid use case for -mno-altivec -mcpu=pwr9
(i.e. don't emit vector code, don't have to save vector regs for context
switch). So we should require the correct features for this lowering.
Fixes https://bugs.llvm.org/show_bug.cgi?id=39334

llvm-svn: 347376

2018-11-21 02:53:50 +00:00

Guozhi Wei

e3b8d9a312

[PPC] Use xxbrd to speed up bswap64

Power doesn't have bswap instructions, so llvm generates following code sequence for bswap64.

  rotldi   5, 3, 16
  rotldi   4, 3, 8
  rotldi   9, 3, 24
  rotldi   10, 3, 32
  rotldi   11, 3, 48
  rotldi   12, 3, 56
  rldimi 4, 5, 8, 48
  rldimi 4, 9, 16, 40
  rldimi 4, 10, 24, 32
  rldimi 4, 11, 40, 16
  rldimi 4, 12, 48, 8
  rldimi 4, 3, 56, 0

But Power9 has vector bswap instructions, they can also be used to speed up scalar bswap intrinsic. With this patch, bswap64 can be translated to:

  mtvsrdd 34, 3, 3
  xxbrd 34, 34
  mfvsrld 3, 34

Differential Revision: https://reviews.llvm.org/D39510

llvm-svn: 317499

2017-11-06 19:09:38 +00:00

3 Commits