Commit Graph

4 Commits

Author SHA1 Message Date
Ulrich Weigand 44d37ae38c [SystemZ] Make better use of VLLEZ
This patch fixes two deficiencies in current code that recognizes
the VLLEZ idiom:

- For the floating-point versions, we have ISel patterns that match
  on a bitconvert as the top node.  In more complex cases, that
  bitconvert may already have been merged into something else.
  Fix the patterns to match the inner nodes instead.

- For the 64-bit integer versions, depending on the surrounding code,
  we may get either a DAG tree based on JOIN_DWORDS or one based on
  INSERT_VECTOR_ELT.  Use a PatFrags to simply match both variants.

llvm-svn: 349749
2018-12-20 13:05:03 +00:00
Ulrich Weigand 80b3af7ab3 [SystemZ] Add CodeGen support for v4f32
The architecture doesn't really have any native v4f32 operations except
v4f32->v2f64 and v2f64->v4f32 conversions, with only half of the v4f32
elements being used.  Even so, using vector registers for <4 x float>
and scalarising individual operations is much better than generating
completely scalar code, since there's much less register pressure.
It's also more efficient to do v4f32 comparisons by extending to 2
v2f64s, comparing those, then packing the result.

This particularly helps with llvmpipe.

Based on a patch by Richard Sandiford.

llvm-svn: 236523
2015-05-05 19:27:45 +00:00
Ulrich Weigand cd808237b2 [SystemZ] Add CodeGen support for v2f64
This adds ABI and CodeGen support for the v2f64 type, which is natively
supported by z13 instructions.

Based on a patch by Richard Sandiford.

llvm-svn: 236522
2015-05-05 19:26:48 +00:00
Ulrich Weigand ce4c109585 [SystemZ] Add CodeGen support for integer vector types
This the first of a series of patches to add CodeGen support exploiting
the instructions of the z13 vector facility.  This patch adds support
for the native integer vector types (v16i8, v8i16, v4i32, v2i64).

When the vector facility is present, we default to the new vector ABI.
This is characterized by two major differences:
- Vector types are passed/returned in vector registers
  (except for unnamed arguments of a variable-argument list function).
- Vector types are at most 8-byte aligned.

The reason for the choice of 8-byte vector alignment is that the hardware
is able to efficiently load vectors at 8-byte alignment, and the ABI only
guarantees 8-byte alignment of the stack pointer, so requiring any higher
alignment for vectors would require dynamic stack re-alignment code.

However, for compatibility with old code that may use vector types, when
*not* using the vector facility, the old alignment rules (vector types
are naturally aligned) remain in use.

These alignment rules are not only implemented at the C language level
(implemented in clang), but also at the LLVM IR level.  This is done
by selecting a different DataLayout string depending on whether the
vector ABI is in effect or not.

Based on a patch by Richard Sandiford.

llvm-svn: 236521
2015-05-05 19:25:42 +00:00