Commit Graph

3 Commits

Author SHA1 Message Date
Arnold Schwaighofer 995ce6c388 TargetLowering: Fix getTypeConversion handling of extended vector types
The code in getTypeConversion attempts to promote the element vector type
before it trys to split or widen the vector.
After it failed finding a legal vector type by promoting it would continue using
the promoted vector element type. Thereby missing legal splitted vector types.
For example the type v32i32 that has a legal split of 4 x v3i32 on x86/sse2
would be transformed to: v32i256 and from there on successively split to:
v16i256, v8i256, v1i256 and then finally ends up as an i64 type.
By resetting the vector element type to the original vector element type that
existed before the promotion the code will attempt to split the vector type to
smaller vector widths of the same type.

llvm-svn: 178999
2013-04-07 20:22:56 +00:00
Arnold Schwaighofer 44f902ed7d X86 cost model: Differentiate cost for vector shifts of constants
SSE2 has efficient support for shifts by a scalar. My previous change of making
shifts expensive did not take this into account marking all shifts as expensive.
This would prevent vectorization from happening where it is actually beneficial.

With this change we differentiate between shifts of constants and other shifts.

radar://13576547

llvm-svn: 178808
2013-04-04 23:26:24 +00:00
Arnold Schwaighofer e9b5016411 X86 cost model: Vector shifts are expensive in most cases
The default logic does not correctly identify costs of casts because they are
marked as custom on x86.

For some cases, where the shift amount is a scalar we would be able to generate
better code. Unfortunately, when this is the case the value (the splat) will get
hoisted out of the loop, thereby making it invisible to ISel.

radar://13130673
radar://13537826

llvm-svn: 178703
2013-04-03 21:46:05 +00:00