llvm-6502/test/CodeGen/X86/vselect-avx.ll
Simon Pilgrim 87d1836793 [X86][SSE] Improve support for 128-bit vector sign extension
This patch improves support for sign extension of the lower lanes of vectors of integers by making use of the SSE41 pmovsx* sign extension instructions where possible, and optimizing the sign extension by shifts on pre-SSE41 targets (avoiding the use of i64 arithmetic shifts which require scalarization).

It converts SIGN_EXTEND nodes to SIGN_EXTEND_VECTOR_INREG where necessary, that more closely matches the pmovsx* instruction than the default approach of using SIGN_EXTEND_INREG which splits the operation (into an ANY_EXTEND lowered to a shuffle followed by shifts) making instruction matching difficult during lowering. Necessary support for SIGN_EXTEND_VECTOR_INREG has been added to the DAGCombiner.

Differential Revision: http://reviews.llvm.org/D9848

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237885 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-21 10:05:03 +00:00

94 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 {{.*#+}} xmm1 = [65533,124,125,14807]
; CHECK: vmovdqa {{.*#+}} xmm1 = [65535,0,0,65535]
; 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: vpsrad $31, %xmm0, %xmm0
; CHECK-NEXT: vpmovsxdq %xmm0, %xmm1
; CHECK-NEXT: vpshufd {{.*#+}} 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*, double** %call1559, i64 %indvars.iv4198
%tmp1888 = load double*, 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
}