llvm-6502/test/CodeGen/X86/vselect-avx.ll
Chandler Carruth b54c36fb4d [x86] Fix PR22706 where we would incorrectly try lower a v32i8 dynamic
blend as legal.

We made the same mistake in two different places. Whenever we are custom
lowering a v32i8 blend we need to check whether we are custom lowering
it only for constant conditions that can be shuffled, or whether we
actually have AVX2 and full dynamic blending support on bytes. Both are
fixed, with comments added to make it clear what is going on and a new
test case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230695 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-26 22:15:34 +00:00

93 lines
4.3 KiB
LLVM

; RUN: llc %s -o - -mattr=+avx | FileCheck %s
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx"
; For this test we used to optimize the <i1 true, i1 false, i1 false, i1 true>
; mask into <i32 2147483648, i32 0, i32 0, i32 2147483648> because we thought
; we would lower that into a blend where only the high bit is relevant.
; However, since the whole mask is constant, this is simplified incorrectly
; by the generic code, because it was expecting -1 in place of 2147483648.
;
; The problem does not occur without AVX, because vselect of v4i32 is not legal
; nor custom.
;
; <rdar://problem/18675020>
; CHECK-LABEL: test:
; CHECK: vmovdqa {{.*#+}} xmm0 = [65535,0,0,65535]
; CHECK: vmovdqa {{.*#+}} xmm2 = [65533,124,125,14807]
; CHECK: ret
define void @test(<4 x i16>* %a, <4 x i16>* %b) {
body:
%predphi = select <4 x i1> <i1 true, i1 false, i1 false, i1 true>, <4 x i16> <i16 -3, i16 545, i16 4385, i16 14807>, <4 x i16> <i16 123, i16 124, i16 125, i16 127>
%predphi42 = select <4 x i1> <i1 true, i1 false, i1 false, i1 true>, <4 x i16> <i16 -1, i16 -1, i16 -1, i16 -1>, <4 x i16> zeroinitializer
store <4 x i16> %predphi, <4 x i16>* %a, align 8
store <4 x i16> %predphi42, <4 x i16>* %b, align 8
ret void
}
; Improve code coverage.
;
; When shrinking the condition used into the select to match a blend, this
; test case exercises the path where the modified node is not the root
; of the condition.
;
; CHECK-LABEL: test2:
; CHECK: vpslld $31, %xmm0, %xmm0
; CHECK-NEXT: vpmovsxdq %xmm0, %xmm1
; CHECK-NEXT: vpshufd $78, %xmm0, %xmm0 ## xmm0 = xmm0[2,3,0,1]
; CHECK-NEXT: vpmovsxdq %xmm0, %xmm0
; CHECK-NEXT: vinsertf128 $1, %xmm0, %ymm1, [[MASK:%ymm[0-9]+]]
; CHECK: vblendvpd [[MASK]]
; CHECK: retq
define void @test2(double** %call1559, i64 %indvars.iv4198, <4 x i1> %tmp1895) {
bb:
%arrayidx1928 = getelementptr inbounds double** %call1559, i64 %indvars.iv4198
%tmp1888 = load double** %arrayidx1928, align 8
%predphi.v.v = select <4 x i1> %tmp1895, <4 x double> <double -5.000000e-01, double -5.000000e-01, double -5.000000e-01, double -5.000000e-01>, <4 x double> <double 5.000000e-01, double 5.000000e-01, double 5.000000e-01, double 5.000000e-01>
%tmp1900 = bitcast double* %tmp1888 to <4 x double>*
store <4 x double> %predphi.v.v, <4 x double>* %tmp1900, align 8
ret void
}
; For this test, we used to optimized the conditional mask for the blend, i.e.,
; we shrunk some of its bits.
; However, this same mask was used in another select (%predphi31) that turned out
; to be optimized into a and. In that case, the conditional mask was wrong.
;
; Make sure that the and is fed by the original mask.
;
; <rdar://problem/18819506>
; CHECK-LABEL: test3:
; Compute the mask.
; CHECK: vpcmpeqd {{%xmm[0-9]+}}, {{%xmm[0-9]+}}, [[MASK:%xmm[0-9]+]]
; Do not shrink the bit of the mask.
; CHECK-NOT: vpslld $31, [[MASK]], {{%xmm[0-9]+}}
; Use the mask in the blend.
; CHECK-NEXT: vblendvps [[MASK]], %xmm{{[0-9]+}}, %xmm{{[0-9]+}}, %xmm{{[0-9]+}}
; Use the mask in the and.
; CHECK-NEXT: vpand LCPI2_2(%rip), [[MASK]], {{%xmm[0-9]+}}
; CHECK: retq
define void @test3(<4 x i32> %induction30, <4 x i16>* %tmp16, <4 x i16>* %tmp17, <4 x i16> %tmp3, <4 x i16> %tmp12) {
%tmp6 = srem <4 x i32> %induction30, <i32 3, i32 3, i32 3, i32 3>
%tmp7 = icmp eq <4 x i32> %tmp6, zeroinitializer
%predphi = select <4 x i1> %tmp7, <4 x i16> %tmp3, <4 x i16> %tmp12
%predphi31 = select <4 x i1> %tmp7, <4 x i16> <i16 -1, i16 -1, i16 -1, i16 -1>, <4 x i16> zeroinitializer
store <4 x i16> %predphi31, <4 x i16>* %tmp16, align 8
store <4 x i16> %predphi, <4 x i16>* %tmp17, align 8
ret void
}
; We shouldn't try to lower this directly using VSELECT because we don't have
; vpblendvb in AVX1, only in AVX2. Instead, it should be expanded.
;
; CHECK-LABEL: PR22706:
; CHECK: vpcmpgtb
; CHECK: vpcmpgtb
define <32 x i8> @PR22706(<32 x i1> %x) {
%tmp = select <32 x i1> %x, <32 x i8> <i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1, i8 1>, <32 x i8> <i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2, i8 2>
ret <32 x i8> %tmp
}