hanchenye-llvm-project/llvm
Hal Finkel 1df3205e8c Adjust PPC A2 input operand latencies
On the PPC A2, instructions are only issued after their input operands are
ready. Model this by specifying that input operands are read at dispatch (0
cycles after issue). This changes all input operand latencies from 1 to 0.

Significant test-suite performance changes (these are 99.5% confidence
intervals on 6 runs for both before and after):

speedups:
MultiSource/Benchmarks/sim/sim
	-1.21915% +/- 0.175063%
MultiSource/Benchmarks/TSVC/LinearDependence-flt/LinearDependence-flt
	-1.23946% +/- 1.05133%
SingleSource/Benchmarks/Misc/flops-2
	-1.24237% +/- 0.681362%
MultiSource/Applications/JM/lencod/lencod
	-1.33992% +/- 0.757498%
MultiSource/Benchmarks/TSVC/InductionVariable-flt/InductionVariable-flt
	-1.51802% +/- 1.21468%
MultiSource/Benchmarks/TSVC/GlobalDataFlow-flt/GlobalDataFlow-flt
	-2.18818% +/- 1.28605%
MultiSource/Benchmarks/TSVC/Packing-flt/Packing-flt
	-2.21977% +/- 1.19499%
SingleSource/Benchmarks/BenchmarkGame/spectral-norm
	-2.29822% +/- 0.671871%
MultiSource/Benchmarks/TSVC/Packing-dbl/Packing-dbl
	-2.40975% +/- 0.355931%
SingleSource/Benchmarks/Misc/fp-convert
	-2.41899% +/- 1.04751%
MultiSource/Benchmarks/TSVC/Searching-dbl/Searching-dbl
	-2.50349% +/- 0.126765%
SingleSource/Benchmarks/Misc/flops-3
	-3.00214% +/- 0.700795%
MultiSource/Benchmarks/TSVC/LoopRestructuring-flt/LoopRestructuring-flt
	-3.56995% +/- 3.2929%
MultiSource/Applications/sgefa/sgefa
	-4.24908% +/- 2.00413%
MultiSource/Benchmarks/ASC_Sequoia/IRSmk/IRSmk
	-18.1294% +/- 3.96489%

regressions:
MultiSource/Benchmarks/TSVC/Reductions-dbl/Reductions-dbl
	1.03249% +/- 0.178547%
MultiSource/Applications/hexxagon/hexxagon
	1.16597% +/- 0.285235%
MultiSource/Benchmarks/TSVC/IndirectAddressing-flt/IndirectAddressing-flt
	1.39576% +/- 1.07855%
SingleSource/Benchmarks/Misc-C++/stepanov_v1p2
	1.71539% +/- 0.173182%
MultiSource/Benchmarks/Fhourstones-3.1/fhourstones3.1
	1.90013% +/- 0.866472%
MultiSource/Benchmarks/TSVC/Recurrences-dbl/Recurrences-dbl
	2.39854% +/- 1.05914%
MultiSource/Benchmarks/TSVC/ControlFlow-dbl/ControlFlow-dbl
	2.4402% +/- 0.817904%
MultiSource/Benchmarks/TSVC/LoopRestructuring-dbl/LoopRestructuring-dbl
	5.87997% +/- 3.3172%
MultiSource/Benchmarks/Trimaran/netbench-crc/netbench-crc
	9.02643% +/- 5.79591%
MultiSource/Benchmarks/VersaBench/bmm/bmm
	10.3517% +/- 1.227%

Obviously, there are data points on both sides of this; but I think, overall,
this supports making the change.

llvm-svn: 195951
2013-11-29 07:04:59 +00:00
..
autoconf Update to reflect the next release. 2013-11-20 10:10:50 +00:00
bindings [OCaml] Add a slash accidentally omitted from Makefile 2013-11-28 09:03:28 +00:00
cmake [CMake] Let add_public_tablegen_target() provide intrinsics_gen, too. 2013-11-28 17:04:31 +00:00
docs [docs] Mention gotcha regarding implicit BB numbering 2013-11-27 04:55:23 +00:00
examples [weak vtables] Place class definitions into anonymous namespaces to prevent weak vtables. 2013-11-19 03:08:35 +00:00
include Refactor a lot of patchpoint/stackmap related code to simplify and make it 2013-11-29 03:07:54 +00:00
lib Adjust PPC A2 input operand latencies 2013-11-29 07:04:59 +00:00
projects Revert "Revert "Windows: Add support for unicode command lines"" 2013-10-07 01:00:07 +00:00
test AArch64: The pattern match should check the range of the immediate value. 2013-11-29 02:11:22 +00:00
tools [PM] Remove the underspecified 'getRoot' method from CallGraph. It's 2013-11-27 01:32:17 +00:00
unittests [CMake] Also OptionTests can be free from add_dependencies() with add_public_tablegen_target(). 2013-11-28 17:04:13 +00:00
utils Default to a better compression algorithm. 2013-11-24 05:29:35 +00:00
.arcconfig
.clang-format Add a clang-format file so that the tool can automatically detect the 2013-09-02 07:19:04 +00:00
.gitignore
CMakeLists.txt CMake : optionaly enable LLVM to be compiled with -std=c++11 (default: off) 2013-11-26 10:33:53 +00:00
CODE_OWNERS.TXT As myself as code-owner of the MIPS backend (lib/Target/Mips/*) 2013-11-28 09:36:44 +00:00
CREDITS.TXT Update CREDITS 2013-11-17 11:44:36 +00:00
LICENSE.TXT
LLVMBuild.txt Remove the very substantial, largely unmaintained legacy PGO 2013-10-02 15:42:23 +00:00
Makefile Remove the very substantial, largely unmaintained legacy PGO 2013-10-02 15:42:23 +00:00
Makefile.common
Makefile.config.in
Makefile.rules Teach the Makefile build system how to handle SOURCES which include 2013-11-14 23:51:29 +00:00
README.txt Revert "Test commit to check e-mail address. Please discard this." 2013-10-04 10:59:13 +00:00
configure Update to reflect the next release. 2013-11-20 10:10:50 +00:00
llvm.spec.in

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