llvm-6502/test
Sanjay Patel 5f79fd2f02 [AVX] Lower / fast-isel scalar FP selects into VBLENDV instructions (PR22483)
This patch reduces code size for all AVX targets and increases speed for some chips.

SSE 4.1 introduced the useless (see code comments) 2-register form of BLENDV and
only in the packed float/double flavors.

AVX subsequently made the instruction useful by adding a 4-register operand form.

So we just need to paper over the lack of scalar forms of this instruction, complicate
the code to choose float or double forms, and use blendv on scalars since all FP is in
xmm registers anyway.

This gives us an approximately 50% speed up for a blendv microbenchmark sequence
on SandyBridge and Haswell:
blendv : 29.73 cycles/iter
logic : 43.15 cycles/iter

No new test cases with this patch because:

1. fast-isel-select-sse.ll tests the positive side for regular X86 lowering and fast-isel
2. sse-minmax.ll and fp-select-cmp-and.ll confirm that we're not firing for scalar selects without AVX
3. fp-select-cmp-and.ll and logical-load-fold.ll confirm that we're not firing for scalar selects with constants.

http://llvm.org/bugs/show_bug.cgi?id=22483

Differential Revision: http://reviews.llvm.org/D8063



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231408 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-05 21:46:54 +00:00
..
Analysis [SCEV] make SCEV smarter about proving no-wrap. 2015-03-04 22:24:17 +00:00
Assembler DebugInfo: Move new hierarchy into place 2015-03-03 17:24:31 +00:00
Bindings DebugInfo: Move new hierarchy into place 2015-03-03 17:24:31 +00:00
Bitcode Make DataLayout Non-Optional in the Module 2015-03-04 18:43:29 +00:00
BugPoint DebugInfo: Move new hierarchy into place 2015-03-03 17:24:31 +00:00
CodeGen [AVX] Lower / fast-isel scalar FP selects into VBLENDV instructions (PR22483) 2015-03-05 21:46:54 +00:00
DebugInfo Use the existing begin and end symbol for debug info. 2015-03-05 02:05:42 +00:00
ExecutionEngine
Feature DebugInfo: Move new hierarchy into place 2015-03-03 17:24:31 +00:00
FileCheck
Instrumentation [sanitizer] add nosanitize metadata to more coverage instrumentation instructions 2015-03-05 01:20:05 +00:00
Integer
JitListener DebugInfo: Move new hierarchy into place 2015-03-03 17:24:31 +00:00
Linker Make DataLayout Non-Optional in the Module 2015-03-04 18:43:29 +00:00
LTO
MC Expand variables when evaluating absolute expressions. 2015-03-04 22:03:21 +00:00
Object
Other Make DataLayout Non-Optional in the Module 2015-03-04 18:43:29 +00:00
SymbolRewriter
TableGen
tools [dsymutil] Add minimal code to emit DIE trees. 2015-03-04 22:07:44 +00:00
Transforms [RewriteStatepointsForGC] Add additional tests around relocation 2015-03-05 19:52:13 +00:00
Unit
Verifier Replace llvm.frameallocate with llvm.frameescape 2015-03-05 18:26:34 +00:00
YAMLParser
.clang-format
CMakeLists.txt
lit.cfg
lit.site.cfg.in
Makefile
Makefile.tests
TestRunner.sh