Commit Graph

4 Commits

Author SHA1 Message Date
Daniel Neilson c8bdc8db73 Change memcpy/memove/memset to have dest and source alignment attributes.
Summary:
  This change is step three in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. Steps:

Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API.
Step 4) Update Polly to use the new IRBuilder API.
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use getDestAlignment()
and getSourceAlignment() instead.
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.

Reference
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

Reviewers: rjmccall

Subscribers: jyknight, nemanjai, nhaehnle, javed.absar, sbc100, aheejin, kbarton, fedor.sergeev, cfe-commits

Differential Revision: https://reviews.llvm.org/D41677

llvm-svn: 323617
2018-01-28 17:27:45 +00:00
Daniel Neilson 6e938effaa Change memcpy/memove/memset to have dest and source alignment attributes (Step 1).
Summary:
  Upstream LLVM is changing the the prototypes of the @llvm.memcpy/memmove/memset
intrinsics. This change updates the Clang tests for this change.

  The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

 This change removes the alignment argument in favour of placing the alignment
attribute on the source and destination pointers of the memory intrinsic call.

 For example, code which used to read:
   call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
   call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

 At this time the source and destination alignments must be the same (Step 1).
Step 2 of the change, to be landed shortly, will relax that contraint and allow
the source and destination to have different alignments.

llvm-svn: 322964
2018-01-19 17:12:54 +00:00
Alex Bradbury 78b2c686b8 [RISCV] Fix test failures on non-assert builds introduced in r322494
Thanks to Eli Friedman, who suggested the reason these tests failed on a few 
buildbots yet works fine locally is because non-assert builds don't emit value 
labels.

llvm-svn: 322514
2018-01-15 20:45:15 +00:00
Alex Bradbury 8cbdd4892f [RISCV] Implement RISCV ABI lowering
RISCVABIInfo is implemented in terms of XLen, supporting both RV32 and RV64. 
Unfortunately we need to count argument registers in the frontend in order to 
determine when to emit signext and zeroext attributes. Integer scalars are 
extended according to their type up to 32-bits and then sign-extended to XLen 
when passed in registers, but are anyext when passed on the stack. This patch 
only implements the base integer (soft float) ABIs.

For more information on the RISC-V ABI, see [the ABI 
doc](https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md), 
my [golden model](https://github.com/lowRISC/riscv-calling-conv-model), and 
the [LLVM RISC-V calling convention 
patch](https://reviews.llvm.org/D39898#2d1595b4) (specifically the comment 
documenting frontend expectations).

Differential Revision: https://reviews.llvm.org/D40023

llvm-svn: 322494
2018-01-15 17:54:52 +00:00