Sanjay Patel b67100314b Fast-math fold: x / (y * sqrt(z)) -> x * (rsqrt(z) / y) ... The motivation is to recognize code such as this from /llvm/projects/test-suite/SingleSource/Benchmarks/BenchmarkGame/n-body.c: float distance = sqrt(dx * dx + dy * dy + dz * dz); float mag = dt / (distance * distance * distance); Without this patch, we don't match the sqrt as a reciprocal sqrt, so for PPC the new testcase in this patch produces: addis 3, 2, .LCPI4_2@toc@ha lfs 4, .LCPI4_2@toc@l(3) addis 3, 2, .LCPI4_1@toc@ha lfs 0, .LCPI4_1@toc@l(3) fcmpu 0, 1, 4 beq 0, .LBB4_2 # BB#1: frsqrtes 4, 1 addis 3, 2, .LCPI4_0@toc@ha lfs 5, .LCPI4_0@toc@l(3) fnmsubs 13, 1, 5, 1 fmuls 6, 4, 4 fmadds 1, 13, 6, 5 fmuls 1, 4, 1 fres 4, 1 <--- reciprocal of reciprocal square root fnmsubs 1, 1, 4, 0 fmadds 4, 4, 1, 4 .LBB4_2: fmuls 1, 4, 2 fres 2, 1 fnmsubs 0, 1, 2, 0 fmadds 0, 2, 0, 2 fmuls 1, 3, 0 blr After the patch, this simplifies to: frsqrtes 0, 1 addis 3, 2, .LCPI4_1@toc@ha fres 5, 2 lfs 4, .LCPI4_1@toc@l(3) addis 3, 2, .LCPI4_0@toc@ha lfs 7, .LCPI4_0@toc@l(3) fnmsubs 13, 1, 4, 1 fmuls 6, 0, 0 fnmsubs 2, 2, 5, 7 fmadds 1, 13, 6, 4 fmadds 2, 5, 2, 5 fmuls 0, 0, 1 fmuls 0, 0, 2 fmuls 1, 3, 0 blr Differential Revision: http://reviews.llvm.org/D5628 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219139 91177308-0d34-0410-b5e6-96231b3b80d8		2014-10-06 19:31:18 +00:00
..
Analysis	[BasicAA] Revert "Revert r218714 - Make better use of zext and sign information."	2014-10-06 18:37:59 +00:00
Assembler	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
Bindings	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
Bitcode	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
BugPoint	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
CodeGen	Fast-math fold: x / (y * sqrt(z)) -> x * (rsqrt(z) / y)	2014-10-06 19:31:18 +00:00
DebugInfo	For biendian targets like ARM and AArch64, it is useful to have the	2014-10-06 07:06:03 +00:00
ExecutionEngine
Feature	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
FileCheck
Instrumentation	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
Integer
JitListener	Revert "Revert "DI: Fold constant arguments into a single MDString""	2014-10-03 20:01:09 +00:00
Linker	[dwarfdump] Print the name for referenced specification of abstract_origin DIEs.	2014-10-06 03:36:31 +00:00
LTO
MC	MachObjectWriter: optimize the string table for common suffices	2014-10-06 17:05:19 +00:00
Object
Other
TableGen
tools	Fix dumping codeview line tables when there are multiple debug sections	2014-10-06 16:59:44 +00:00
Transforms	Give the Reassociate pass a bit more flexibility and autonomy when optimizing expressions.	2014-10-05 23:41:26 +00:00
Unit
Verifier
YAMLParser
.clang-format
CMakeLists.txt
lit.cfg
lit.site.cfg.in
Makefile
Makefile.tests
TestRunner.sh