2015-02-04 00:58:40 +00:00
|
|
|
; RUN: llc -mtriple=x86_64-unknown-unknown -mattr=+sse2 < %s | FileCheck %s --check-prefix=SSE2
|
|
|
|
|
; RUN: llc -mtriple=x86_64-unknown-unknown -mattr=+avx < %s | FileCheck %s --check-prefix=AVX
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
|
|
|
|
|
define <8 x i16> @test1(<8 x i16> %A, <8 x i16> %B) {
|
|
|
|
|
; SSE2-LABEL: test1:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: movd %xmm1, %eax
|
|
|
|
|
; SSE2-NEXT: movzwl %ax, %eax
|
|
|
|
|
; SSE2-NEXT: movd %eax, %xmm1
|
|
|
|
|
; SSE2-NEXT: psllw %xmm1, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test1:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
|
|
|
|
|
; AVX-NEXT: vpblendw {{.*#+}} xmm1 = xmm1[0],xmm2[1,2,3,4,5,6,7]
|
|
|
|
|
; AVX-NEXT: vpsllw %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit14 = shufflevector <8 x i16> %B, <8 x i16> undef, <8 x i32> zeroinitializer
|
|
|
|
|
%shl = shl <8 x i16> %A, %vecinit14
|
|
|
|
|
ret <8 x i16> %shl
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <4 x i32> @test2(<4 x i32> %A, <4 x i32> %B) {
|
|
|
|
|
; SSE2-LABEL: test2:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: xorps %xmm2, %xmm2
|
|
|
|
|
; SSE2-NEXT: movss {{.*#+}} xmm2 = xmm1[0],xmm2[1,2,3]
|
|
|
|
|
; SSE2-NEXT: pslld %xmm2, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test2:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
|
|
|
|
|
; AVX-NEXT: vpblendw {{.*#+}} xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
|
|
|
|
|
; AVX-NEXT: vpslld %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit6 = shufflevector <4 x i32> %B, <4 x i32> undef, <4 x i32> zeroinitializer
|
|
|
|
|
%shl = shl <4 x i32> %A, %vecinit6
|
|
|
|
|
ret <4 x i32> %shl
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <2 x i64> @test3(<2 x i64> %A, <2 x i64> %B) {
|
|
|
|
|
; SSE2-LABEL: test3:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: psllq %xmm1, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test3:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpsllq %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit2 = shufflevector <2 x i64> %B, <2 x i64> undef, <2 x i32> zeroinitializer
|
|
|
|
|
%shl = shl <2 x i64> %A, %vecinit2
|
|
|
|
|
ret <2 x i64> %shl
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <8 x i16> @test4(<8 x i16> %A, <8 x i16> %B) {
|
|
|
|
|
; SSE2-LABEL: test4:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: movd %xmm1, %eax
|
|
|
|
|
; SSE2-NEXT: movzwl %ax, %eax
|
|
|
|
|
; SSE2-NEXT: movd %eax, %xmm1
|
|
|
|
|
; SSE2-NEXT: psrlw %xmm1, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test4:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
|
|
|
|
|
; AVX-NEXT: vpblendw {{.*#+}} xmm1 = xmm1[0],xmm2[1,2,3,4,5,6,7]
|
|
|
|
|
; AVX-NEXT: vpsrlw %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit14 = shufflevector <8 x i16> %B, <8 x i16> undef, <8 x i32> zeroinitializer
|
|
|
|
|
%shr = lshr <8 x i16> %A, %vecinit14
|
|
|
|
|
ret <8 x i16> %shr
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <4 x i32> @test5(<4 x i32> %A, <4 x i32> %B) {
|
|
|
|
|
; SSE2-LABEL: test5:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: xorps %xmm2, %xmm2
|
|
|
|
|
; SSE2-NEXT: movss {{.*#+}} xmm2 = xmm1[0],xmm2[1,2,3]
|
|
|
|
|
; SSE2-NEXT: psrld %xmm2, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test5:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
|
|
|
|
|
; AVX-NEXT: vpblendw {{.*#+}} xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
|
|
|
|
|
; AVX-NEXT: vpsrld %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit6 = shufflevector <4 x i32> %B, <4 x i32> undef, <4 x i32> zeroinitializer
|
|
|
|
|
%shr = lshr <4 x i32> %A, %vecinit6
|
|
|
|
|
ret <4 x i32> %shr
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <2 x i64> @test6(<2 x i64> %A, <2 x i64> %B) {
|
|
|
|
|
; SSE2-LABEL: test6:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: psrlq %xmm1, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test6:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpsrlq %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit2 = shufflevector <2 x i64> %B, <2 x i64> undef, <2 x i32> zeroinitializer
|
|
|
|
|
%shr = lshr <2 x i64> %A, %vecinit2
|
|
|
|
|
ret <2 x i64> %shr
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <8 x i16> @test7(<8 x i16> %A, <8 x i16> %B) {
|
|
|
|
|
; SSE2-LABEL: test7:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: movd %xmm1, %eax
|
|
|
|
|
; SSE2-NEXT: movzwl %ax, %eax
|
|
|
|
|
; SSE2-NEXT: movd %eax, %xmm1
|
|
|
|
|
; SSE2-NEXT: psraw %xmm1, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test7:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
|
|
|
|
|
; AVX-NEXT: vpblendw {{.*#+}} xmm1 = xmm1[0],xmm2[1,2,3,4,5,6,7]
|
|
|
|
|
; AVX-NEXT: vpsraw %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit14 = shufflevector <8 x i16> %B, <8 x i16> undef, <8 x i32> zeroinitializer
|
|
|
|
|
%shr = ashr <8 x i16> %A, %vecinit14
|
|
|
|
|
ret <8 x i16> %shr
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <4 x i32> @test8(<4 x i32> %A, <4 x i32> %B) {
|
|
|
|
|
; SSE2-LABEL: test8:
|
2015-02-04 00:58:40 +00:00
|
|
|
; SSE2: # BB#0: # %entry
|
|
|
|
|
; SSE2-NEXT: xorps %xmm2, %xmm2
|
|
|
|
|
; SSE2-NEXT: movss {{.*#+}} xmm2 = xmm1[0],xmm2[1,2,3]
|
|
|
|
|
; SSE2-NEXT: psrad %xmm2, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; SSE2-NEXT: retq
|
2015-02-04 00:58:40 +00:00
|
|
|
;
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-LABEL: test8:
|
2015-02-04 00:58:40 +00:00
|
|
|
; AVX: # BB#0: # %entry
|
|
|
|
|
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
|
|
|
|
|
; AVX-NEXT: vpblendw {{.*#+}} xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
|
|
|
|
|
; AVX-NEXT: vpsrad %xmm1, %xmm0, %xmm0
|
[X86] Avoid introducing extra shuffles when lowering packed vector shifts.
When lowering a vector shift node, the backend checks if the shift count is a
shuffle with a splat mask. If so, then it introduces an extra dag node to
extract the splat value from the shuffle. The splat value is then used
to generate a shift count of a target specific shift.
However, if we know that the shift count is a splat shuffle, we can use the
splat index 'I' to extract the I-th element from the first shuffle operand.
The advantage is that the splat shuffle may become dead since we no longer
use it.
Example:
;;
define <4 x i32> @example(<4 x i32> %a, <4 x i32> %b) {
%c = shufflevector <4 x i32> %b, <4 x i32> undef, <4 x i32> zeroinitializer
%shl = shl <4 x i32> %a, %c
ret <4 x i32> %shl
}
;;
Before this patch, llc generated the following code (-mattr=+avx):
vpshufd $0, %xmm1, %xmm1 # xmm1 = xmm1[0,0,0,0]
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
With this patch, the redundant splat operation is removed from the code.
vpxor %xmm2, %xmm2
vpblendw $3, %xmm1, %xmm2, %xmm1 # xmm1 = xmm1[0,1],xmm2[2,3,4,5,6,7]
vpslld %xmm1, %xmm0, %xmm0
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223461 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 12:13:30 +00:00
|
|
|
; AVX-NEXT: retq
|
|
|
|
|
entry:
|
|
|
|
|
%vecinit6 = shufflevector <4 x i32> %B, <4 x i32> undef, <4 x i32> zeroinitializer
|
|
|
|
|
%shr = ashr <4 x i32> %A, %vecinit6
|
|
|
|
|
ret <4 x i32> %shr
|
|
|
|
|
}
|
