[PATCH] D105666: [PowerPC] [Altivec] Use signed comparison for vec_all_* and vec_any_* interfaces that compare vector bool types with vector signed types

[Bardia Mahjour via Phabricator via cfe-commits]

bmahjour created this revision.
bmahjour added reviewers: nemanjai, cebowleratibm, PowerPC, rzurob.
bmahjour added projects: PowerPC, LLVM.
Herald added subscribers: shchenz, kbarton.
bmahjour requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

We are currently being inconsistent in using signed vs unsigned comparisons for vec_all_* and vec_any_* interfaces that use vector bool types. For example we use signed comparison for `vec_all_ge(vector signed char, vector bool char)` but unsigned comparison for when the arguments are swapped. GCC and XL use signed comparison instead. This patch makes clang consistent with XL and GCC.

Example:

  #include <stdio.h>
  #include <altivec.h>
  int main() {
    vector signed char a = {0,0,0,0,0,0,0xA3,0,0,0x89,0,0,0xA4,0,0,0};
    vector bool char b = {0,0,0,0,0,0,0xF3,0,0,0x61,0,0,0xAE,0,0,0};
    printf(" a >= b : %d\n b >= a : %d\n", vec_all_ge(a, b), vec_all_ge(b, a));
    return 0;
  }

currently produces

  a >= b : 0
  b >= a : 0

with this patch we get:

  a >= b : 0
  b >= a : 1


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D105666

Files:
  clang/lib/Headers/altivec.h
  clang/test/CodeGen/builtins-ppc-altivec.c
  clang/test/CodeGen/builtins-ppc-vsx.c

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