Files
clang-p2996/llvm/test/Transforms/LoopVectorize/X86/avx512.ll
Craig Topper 0d797a34d8 [X86] Add support for passing 'prefer-vector-width' function attribute into X86Subtarget and exposing via X86's getRegisterWidth TTI interface.
This will cause the vectorizers to do some limiting of the vector widths they create. This is not a strict limit. There are reasons I know of that the loop vectorizer will generate larger vectors for.

I've written this in such a way that the interface will only return a properly supported width(0/128/256/512) even if the attribute says something funny like 384 or 10.

This has been split from D41895 with the remainder in a follow up commit.

llvm-svn: 323015
2018-01-20 00:26:08 +00:00

113 lines
3.9 KiB
LLVM

; RUN: opt -mattr=+avx512f --loop-vectorize -S < %s | llc -mattr=+avx512f | FileCheck %s
; RUN: opt -mattr=+avx512vl,+prefer-256-bit --loop-vectorize -S < %s | llc -mattr=+avx512f | FileCheck %s --check-prefix=CHECK-PREFER-AVX256
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.9.0"
; Verify that we generate 512-bit wide vectors for a basic integer memset
; loop.
; CHECK-LABEL: f:
; CHECK: vmovdqu64 %zmm{{.}},
; CHECK-NOT: %ymm
; Verify that we don't generate 512-bit wide vectors when subtarget feature says not to
; CHECK-PREFER-AVX256-LABEL: f:
; CHECK-PREFER-AVX256: vmovdqu %ymm{{.}},
; CHECK-PREFER-AVX256-NOT: %zmm
define void @f(i32* %a, i32 %n) {
entry:
%cmp4 = icmp sgt i32 %n, 0
br i1 %cmp4, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
br label %for.body
for.body: ; preds = %for.body.preheader, %for.body
%indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]
%arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
store i32 %n, i32* %arrayidx, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, %n
br i1 %exitcond, label %for.end.loopexit, label %for.body
for.end.loopexit: ; preds = %for.body
br label %for.end
for.end: ; preds = %for.end.loopexit, %entry
ret void
}
; Verify that the "prefer-vector-width=256" attribute prevents the use of 512-bit
; vectors
; CHECK-LABEL: g:
; CHECK: vmovdqu %ymm{{.}},
; CHECK-NOT: %zmm
; CHECK-PREFER-AVX256-LABEL: g:
; CHECK-PREFER-AVX256: vmovdqu %ymm{{.}},
; CHECK-PREFER-AVX256-NOT: %zmm
define void @g(i32* %a, i32 %n) "prefer-vector-width"="256" {
entry:
%cmp4 = icmp sgt i32 %n, 0
br i1 %cmp4, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
br label %for.body
for.body: ; preds = %for.body.preheader, %for.body
%indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]
%arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
store i32 %n, i32* %arrayidx, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, %n
br i1 %exitcond, label %for.end.loopexit, label %for.body
for.end.loopexit: ; preds = %for.body
br label %for.end
for.end: ; preds = %for.end.loopexit, %entry
ret void
}
; Verify that the "prefer-vector-width=512" attribute override the subtarget
; vectors
; CHECK-LABEL: h:
; CHECK: vmovdqu64 %zmm{{.}},
; CHECK-NOT: %ymm
; CHECK-PREFER-AVX256-LABEL: h:
; CHECK-PREFER-AVX256: vmovdqu64 %zmm{{.}},
; CHECK-PREFER-AVX256-NOT: %ymm
define void @h(i32* %a, i32 %n) "prefer-vector-width"="512" {
entry:
%cmp4 = icmp sgt i32 %n, 0
br i1 %cmp4, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
br label %for.body
for.body: ; preds = %for.body.preheader, %for.body
%indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]
%arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
store i32 %n, i32* %arrayidx, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, %n
br i1 %exitcond, label %for.end.loopexit, label %for.body
for.end.loopexit: ; preds = %for.body
br label %for.end
for.end: ; preds = %for.end.loopexit, %entry
ret void
}