Commit Graph

9 Commits

Author SHA1 Message Date
Elena Demikhovsky 291fe0159f VX-512: Fixed a bug in FP logic operation lowering
FP logic instructions are supported in DQ extension on AVX-512 target.
I use integer operations instead.
Added tests.
I also enabled FABS in this patch in order to check ANDPS.
The operations are FOR, FXOR, FAND, FANDN.
The instructions, that supported for 512-bit vector under DQ are:
VORPS/PD, VXORPS/PD, VANDPS/PD, FANDNPS/PD.

Differential Revision: http://reviews.llvm.org/D15110

llvm-svn: 254913
2015-12-07 14:33:34 +00:00
Sanjay Patel 8c13e3680d fix invalid load folding with SSE/AVX FP logical instructions (PR22371)
This is a follow-up to the FIXME that was added with D7474 ( http://reviews.llvm.org/rL229531 ).
I thought this load folding bug had been made hard-to-hit, but it turns out to be very easy
when targeting 32-bit x86 and causes a miscompile/crash in Wine:
https://bugs.winehq.org/show_bug.cgi?id=38826
https://llvm.org/bugs/show_bug.cgi?id=22371#c25

The quick fix is to simply remove the scalar FP logical instructions from the load folding table
in X86InstrInfo, but that causes us to miss load folds that should be possible when lowering fabs,
fneg, fcopysign. So the majority of this patch is altering those lowerings to use *vector* FP
logical instructions (because that's all x86 gives us anyway). That lets us do the load folding 
legally.

Differential Revision: http://reviews.llvm.org/D11477

llvm-svn: 243361
2015-07-28 00:48:32 +00:00
Sanjay Patel afe251649b fixed to test features, not CPUs
llvm-svn: 228836
2015-02-11 15:00:41 +00:00
Sanjay Patel 1954f2e924 Improved test cases that were added with r214892.
1. Added ':' to CHECK-LABELs
2. Added more CHECKs
3. Added CHECK-NEXTs
4. Added verbose hex immediate comments to CHECKs

llvm-svn: 214921
2014-08-05 20:16:35 +00:00
Sanjay Patel 8e5beb6edb Optimize vector fabs of bitcasted constant integer values.
Allow vector fabs operations on bitcasted constant integer values to be optimized
in the same way that we already optimize scalar fabs.

So for code like this:
%bitcast = bitcast i64 18446744069414584320 to <2 x float> ; 0xFFFF_FFFF_0000_0000
%fabs = call <2 x float> @llvm.fabs.v2f32(<2 x float> %bitcast)
%ret = bitcast <2 x float> %fabs to i64

Instead of generating something like this:

movabsq (constant pool loadi of mask for sign bits)
vmovq   (move from integer register to vector/fp register)
vandps  (mask off sign bits)
vmovq   (move vector/fp register back to integer return register)

We should generate:

mov     (put constant value in return register)

I have also removed a redundant clause in the first 'if' statement:
N0.getOperand(0).getValueType().isInteger()

is the same thing as:
IntVT.isInteger()

Testcases for x86 and ARM added to existing files that deal with vector fabs.
One existing testcase for x86 removed because it is no longer ideal.

For more background, please see:
http://reviews.llvm.org/D4770

And:
http://llvm.org/bugs/show_bug.cgi?id=20354

Differential Revision: http://reviews.llvm.org/D4785

llvm-svn: 214892
2014-08-05 17:35:22 +00:00
Chandler Carruth 7bbfd245b0 [x86] Fix the test case added in r214670 and tweaked in r214674 further.
Fundamentally, there isn't a really portable way to test the constant
pool contents. Instead, pin this test to the bare-metal triple. This
also makes it a 64-bit triple which allows us to only match a single
constant pool rather than two. It can also just hard code the '.' prefix
as the format should be stable now that it has a fixed triple. Finally,
I've switched it to use CHECK-NEXT to be more precise in the instruction
sequence expected and to use variables rather than hard coding decisions
by the register allocator.

llvm-svn: 214679
2014-08-04 00:54:28 +00:00
Sanjay Patel 065cabf43e Account for possible leading '.' in label string.
llvm-svn: 214674
2014-08-03 23:20:16 +00:00
Sanjay Patel 2ef67440fc fix for PR20354 - Miscompile of fabs due to vectorization
This is intended to be the minimal change needed to fix PR20354 ( http://llvm.org/bugs/show_bug.cgi?id=20354 ). The check for a vector operation was wrong; we need to check that the fabs itself is not a vector operation.

This patch will not generate the optimal code. A constant pool load and 'and' op will be generated instead of just returning a value that we can calculate in advance (as we do for the scalar case). I've put a 'TODO' comment for that here and expect to have that patch ready soon.

There is a very similar optimization that we can do in visitFNEG, so I've put another 'TODO' there and expect to have another patch for that too.

llvm-svn: 214670
2014-08-03 22:48:23 +00:00
Craig Topper 98f2e861a0 Add support for lowering FABS of vector types.
llvm-svn: 163461
2012-09-08 07:31:51 +00:00