[llvm] r296137 - [DAGCombiner] add missing folds for scalar select of {-1, 0, 1}
Sanjay Patel via llvm-commits
llvm-commits at lists.llvm.org
Fri Feb 24 09:17:33 PST 2017
Author: spatel
Date: Fri Feb 24 11:17:33 2017
New Revision: 296137
URL: http://llvm.org/viewvc/llvm-project?rev=296137&view=rev
Log:
[DAGCombiner] add missing folds for scalar select of {-1,0,1}
The motivation for filling out these select-of-constants cases goes back to D24480,
where we discussed removing an IR fold from add(zext) --> select. And that goes back to:
https://reviews.llvm.org/rL75531
https://reviews.llvm.org/rL159230
The idea is that we should always canonicalize patterns like this to a select-of-constants
in IR because that's the smallest IR and the best for value tracking. Note that we currently
do the opposite in some cases (like the cases in *this* patch). Ie, the proposed folds in
this patch already exist in InstCombine today:
https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineSelect.cpp#L1151
As this patch shows, most targets generate better machine code for simple ext/add/not ops
rather than a select of constants. So the follow-up steps to make this less of a patchwork
of special-case folds and missing IR canonicalization:
1. Have DAGCombiner convert any select of constants into ext/add/not ops.
2 Have InstCombine canonicalize in the other direction (create more selects).
Differential Revision: https://reviews.llvm.org/D30180
Modified:
llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
llvm/trunk/test/CodeGen/AMDGPU/trunc.ll
llvm/trunk/test/CodeGen/ARM/select_const.ll
llvm/trunk/test/CodeGen/Hexagon/adde.ll
llvm/trunk/test/CodeGen/Hexagon/sube.ll
llvm/trunk/test/CodeGen/NVPTX/add-128bit.ll
llvm/trunk/test/CodeGen/PowerPC/select_const.ll
llvm/trunk/test/CodeGen/X86/select_const.ll
Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Fri Feb 24 11:17:33 2017
@@ -5599,8 +5599,13 @@ SDValue DAGCombiner::foldSelectOfConstan
if (!isa<ConstantSDNode>(N1) || !isa<ConstantSDNode>(N2))
return SDValue();
- // TODO: We should handle other cases of selecting between {-1,0,1} here.
- if (CondVT == MVT::i1) {
+ // Only do this before legalization to avoid conflicting with target-specific
+ // transforms in the other direction (create a select from a zext/sext). There
+ // is also a target-independent combine here in DAGCombiner in the other
+ // direction for (select Cond, -1, 0) when the condition is not i1.
+ // TODO: This could be generalized for any 2 constants that differ by 1:
+ // add ({s/z}ext Cond), C
+ if (CondVT == MVT::i1 && !LegalOperations) {
if (isNullConstant(N1) && isOneConstant(N2)) {
// select Cond, 0, 1 --> zext (!Cond)
SDValue NotCond = DAG.getNOT(DL, Cond, MVT::i1);
@@ -5608,6 +5613,25 @@ SDValue DAGCombiner::foldSelectOfConstan
NotCond = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, NotCond);
return NotCond;
}
+ if (isNullConstant(N1) && isAllOnesConstant(N2)) {
+ // select Cond, 0, -1 --> sext (!Cond)
+ SDValue NotCond = DAG.getNOT(DL, Cond, MVT::i1);
+ if (VT != MVT::i1)
+ NotCond = DAG.getNode(ISD::SIGN_EXTEND, DL, VT, NotCond);
+ return NotCond;
+ }
+ if (isOneConstant(N1) && isNullConstant(N2)) {
+ // select Cond, 1, 0 --> zext (Cond)
+ if (VT != MVT::i1)
+ Cond = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, Cond);
+ return Cond;
+ }
+ if (isAllOnesConstant(N1) && isNullConstant(N2)) {
+ // select Cond, -1, 0 --> sext (Cond)
+ if (VT != MVT::i1)
+ Cond = DAG.getNode(ISD::SIGN_EXTEND, DL, VT, Cond);
+ return Cond;
+ }
return SDValue();
}
@@ -6766,7 +6790,12 @@ SDValue DAGCombiner::visitSIGN_EXTEND(SD
if (!VT.isVector()) {
EVT SetCCVT = getSetCCResultType(N00VT);
- if (!LegalOperations || TLI.isOperationLegal(ISD::SETCC, N00VT)) {
+ // Don't do this transform for i1 because there's a select transform
+ // that would reverse it.
+ // TODO: We should not do this transform at all without a target hook
+ // because a sext is likely cheaper than a select?
+ if (SetCCVT.getScalarSizeInBits() != 1 &&
+ (!LegalOperations || TLI.isOperationLegal(ISD::SETCC, N00VT))) {
SDValue SetCC = DAG.getSetCC(DL, SetCCVT, N00, N01, CC);
return DAG.getSelect(DL, VT, SetCC, ExtTrueVal, Zero);
}
Modified: llvm/trunk/test/CodeGen/AMDGPU/trunc.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/trunc.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/trunc.ll (original)
+++ llvm/trunk/test/CodeGen/AMDGPU/trunc.ll Fri Feb 24 11:17:33 2017
@@ -56,8 +56,7 @@ define void @trunc_shl_i64(i64 addrspace
}
; GCN-LABEL: {{^}}trunc_i32_to_i1:
-; GCN: v_and_b32_e32 v{{[0-9]+}}, 1, v{{[0-9]+}}
-; GCN: v_cmp_eq_u32
+; GCN: v_and_b32_e32 [[VREG:v[0-9]+]], 1, v{{[0-9]+}}
define void @trunc_i32_to_i1(i32 addrspace(1)* %out, i32 addrspace(1)* %ptr) {
%a = load i32, i32 addrspace(1)* %ptr, align 4
%trunc = trunc i32 %a to i1
@@ -67,8 +66,7 @@ define void @trunc_i32_to_i1(i32 addrspa
}
; GCN-LABEL: {{^}}trunc_i8_to_i1:
-; GCN: v_and_b32_e32 v{{[0-9]+}}, 1, v{{[0-9]+}}
-; GCN: v_cmp_eq_u32
+; GCN: v_and_b32_e32 [[VREG:v[0-9]+]], 1, v{{[0-9]+}}
define void @trunc_i8_to_i1(i8 addrspace(1)* %out, i8 addrspace(1)* %ptr) {
%a = load i8, i8 addrspace(1)* %ptr, align 4
%trunc = trunc i8 %a to i1
@@ -78,8 +76,7 @@ define void @trunc_i8_to_i1(i8 addrspace
}
; GCN-LABEL: {{^}}sgpr_trunc_i16_to_i1:
-; GCN: s_and_b32 s{{[0-9]+}}, 1, s{{[0-9]+}}
-; GCN: v_cmp_eq_u32
+; GCN: s_and_b32 s{{[0-9]+}}, s{{[0-9]+}}, 1
define void @sgpr_trunc_i16_to_i1(i16 addrspace(1)* %out, i16 %a) {
%trunc = trunc i16 %a to i1
%result = select i1 %trunc, i16 1, i16 0
@@ -88,8 +85,7 @@ define void @sgpr_trunc_i16_to_i1(i16 ad
}
; GCN-LABEL: {{^}}sgpr_trunc_i32_to_i1:
-; GCN: s_and_b32 s{{[0-9]+}}, 1, s{{[0-9]+}}
-; GCN: v_cmp_eq_u32
+; GCN: s_and_b32 s{{[0-9]+}}, s{{[0-9]+}}, 1
define void @sgpr_trunc_i32_to_i1(i32 addrspace(1)* %out, i32 %a) {
%trunc = trunc i32 %a to i1
%result = select i1 %trunc, i32 1, i32 0
Modified: llvm/trunk/test/CodeGen/ARM/select_const.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/select_const.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/select_const.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/select_const.ll Fri Feb 24 11:17:33 2017
@@ -40,8 +40,7 @@ define i32 @select_0_or_1_signext(i1 sig
define i32 @select_1_or_0(i1 %cond) {
; CHECK-LABEL: select_1_or_0:
; CHECK: @ BB#0:
-; CHECK-NEXT: ands r0, r0, #1
-; CHECK-NEXT: movne r0, #1
+; CHECK-NEXT: and r0, r0, #1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
@@ -50,8 +49,6 @@ define i32 @select_1_or_0(i1 %cond) {
define i32 @select_1_or_0_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_1_or_0_zeroext:
; CHECK: @ BB#0:
-; CHECK-NEXT: cmp r0, #0
-; CHECK-NEXT: movne r0, #1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
@@ -60,8 +57,7 @@ define i32 @select_1_or_0_zeroext(i1 zer
define i32 @select_1_or_0_signext(i1 signext %cond) {
; CHECK-LABEL: select_1_or_0_signext:
; CHECK: @ BB#0:
-; CHECK-NEXT: ands r0, r0, #1
-; CHECK-NEXT: movne r0, #1
+; CHECK-NEXT: and r0, r0, #1
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
@@ -72,10 +68,9 @@ define i32 @select_1_or_0_signext(i1 sig
define i32 @select_0_or_neg1(i1 %cond) {
; CHECK-LABEL: select_0_or_neg1:
; CHECK: @ BB#0:
-; CHECK-NEXT: mvn r1, #0
-; CHECK-NEXT: tst r0, #1
-; CHECK-NEXT: movne r1, #0
-; CHECK-NEXT: mov r0, r1
+; CHECK-NEXT: mov r1, #1
+; CHECK-NEXT: bic r0, r1, r0
+; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 -1
ret i32 %sel
@@ -84,10 +79,8 @@ define i32 @select_0_or_neg1(i1 %cond) {
define i32 @select_0_or_neg1_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_0_or_neg1_zeroext:
; CHECK: @ BB#0:
-; CHECK-NEXT: mvn r1, #0
-; CHECK-NEXT: cmp r0, #0
-; CHECK-NEXT: movne r1, #0
-; CHECK-NEXT: mov r0, r1
+; CHECK-NEXT: eor r0, r0, #1
+; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 -1
ret i32 %sel
@@ -96,10 +89,7 @@ define i32 @select_0_or_neg1_zeroext(i1
define i32 @select_0_or_neg1_signext(i1 signext %cond) {
; CHECK-LABEL: select_0_or_neg1_signext:
; CHECK: @ BB#0:
-; CHECK-NEXT: mvn r1, #0
-; CHECK-NEXT: tst r0, #1
-; CHECK-NEXT: movne r1, #0
-; CHECK-NEXT: mov r0, r1
+; CHECK-NEXT: mvn r0, r0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 0, i32 -1
ret i32 %sel
@@ -110,8 +100,8 @@ define i32 @select_0_or_neg1_signext(i1
define i32 @select_neg1_or_0(i1 %cond) {
; CHECK-LABEL: select_neg1_or_0:
; CHECK: @ BB#0:
-; CHECK-NEXT: ands r0, r0, #1
-; CHECK-NEXT: mvnne r0, #0
+; CHECK-NEXT: and r0, r0, #1
+; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
@@ -120,8 +110,7 @@ define i32 @select_neg1_or_0(i1 %cond) {
define i32 @select_neg1_or_0_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_neg1_or_0_zeroext:
; CHECK: @ BB#0:
-; CHECK-NEXT: cmp r0, #0
-; CHECK-NEXT: mvnne r0, #0
+; CHECK-NEXT: rsb r0, r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
@@ -130,8 +119,6 @@ define i32 @select_neg1_or_0_zeroext(i1
define i32 @select_neg1_or_0_signext(i1 signext %cond) {
; CHECK-LABEL: select_neg1_or_0_signext:
; CHECK: @ BB#0:
-; CHECK-NEXT: ands r0, r0, #1
-; CHECK-NEXT: mvnne r0, #0
; CHECK-NEXT: mov pc, lr
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
Modified: llvm/trunk/test/CodeGen/Hexagon/adde.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Hexagon/adde.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/Hexagon/adde.ll (original)
+++ llvm/trunk/test/CodeGen/Hexagon/adde.ll Fri Feb 24 11:17:33 2017
@@ -1,13 +1,12 @@
; RUN: llc -march=hexagon -disable-hsdr -hexagon-expand-condsets=0 -hexagon-bit=0 -disable-post-ra < %s | FileCheck %s
-; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,#1)
-; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,#0)
; CHECK: r{{[0-9]+:[0-9]+}} = add(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
+; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,#1)
; CHECK: p{{[0-9]+}} = cmp.gtu(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
; CHECK: p{{[0-9]+}} = cmp.gtu(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
-; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},r{{[0-9]+}},r{{[0-9]+}})
-; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},r{{[0-9]+}},r{{[0-9]+}})
-; CHECK: r{{[0-9]+:[0-9]+}} = combine(r{{[0-9]+}},r{{[0-9]+}})
+; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},#1,#0)
+; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,r{{[0-9]+}})
+; CHECK: r{{[0-9]+:[0-9]+}} = add(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},r{{[0-9]+}},r{{[0-9]+}})
; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},r{{[0-9]+}},r{{[0-9]+}})
; CHECK: r{{[0-9]+:[0-9]+}} = combine(r{{[0-9]+}},r{{[0-9]+}})
Modified: llvm/trunk/test/CodeGen/Hexagon/sube.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Hexagon/sube.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/Hexagon/sube.ll (original)
+++ llvm/trunk/test/CodeGen/Hexagon/sube.ll Fri Feb 24 11:17:33 2017
@@ -1,13 +1,11 @@
; RUN: llc -march=hexagon -disable-hsdr -hexagon-expand-condsets=0 -hexagon-bit=0 -disable-post-ra < %s | FileCheck %s
-; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,#0)
-; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,#1)
; CHECK: p{{[0-9]+}} = cmp.gtu(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
; CHECK: r{{[0-9]+:[0-9]+}} = sub(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
-; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},r{{[0-9]+}},r{{[0-9]+}})
-; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},r{{[0-9]+}},r{{[0-9]+}})
+; CHECK: r{{[0-9]+}} = mux(p{{[0-9]+}},#1,#0
+; CHECK: r{{[0-9]+:[0-9]+}} = sub(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
+; CHECK: r{{[0-9]+:[0-9]+}} = combine(#0,r{{[0-9]+}})
; CHECK: r{{[0-9]+:[0-9]+}} = sub(r{{[0-9]+:[0-9]+}},r{{[0-9]+:[0-9]+}})
-; CHECK: r{{[0-9]+:[0-9]+}} = combine(r{{[0-9]+}},r{{[0-9]+}})
define void @check_sube_subc(i64 %AL, i64 %AH, i64 %BL, i64 %BH, i64* %RL, i64* %RH) {
entry:
Modified: llvm/trunk/test/CodeGen/NVPTX/add-128bit.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/NVPTX/add-128bit.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/NVPTX/add-128bit.ll (original)
+++ llvm/trunk/test/CodeGen/NVPTX/add-128bit.ll Fri Feb 24 11:17:33 2017
@@ -8,7 +8,7 @@ define void @foo(i64 %a, i64 %add, i128*
; CHECK: add.s64
; CHECK: setp.lt.u64
; CHECK: setp.lt.u64
-; CHECK: selp.b64
+; CHECK: selp.u64
; CHECK: selp.b64
; CHECK: add.s64
%t1 = sext i64 %a to i128
Modified: llvm/trunk/test/CodeGen/PowerPC/select_const.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/select_const.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/select_const.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/select_const.ll Fri Feb 24 11:17:33 2017
@@ -39,70 +39,27 @@ define i32 @select_0_or_1_signext(i1 sig
; select Cond, 1, 0 --> zext (Cond)
define i32 @select_1_or_0(i1 %cond) {
-; ISEL-LABEL: select_1_or_0:
-; ISEL: # BB#0:
-; ISEL-NEXT: andi. 3, 3, 1
-; ISEL-NEXT: li 4, 1
-; ISEL-NEXT: li 3, 0
-; ISEL-NEXT: isel 3, 4, 3, 1
-; ISEL-NEXT: blr
-;
-; NO_ISEL-LABEL: select_1_or_0:
-; NO_ISEL: # BB#0:
-; NO_ISEL-NEXT: andi. 3, 3, 1
-; NO_ISEL-NEXT: li 4, 1
-; NO_ISEL-NEXT: li 3, 0
-; NO_ISEL-NEXT: bc 12, 1, .LBB3_1
-; NO_ISEL-NEXT: blr
-; NO_ISEL-NEXT: .LBB3_1:
-; NO_ISEL-NEXT: addi 3, 4, 0
-; NO_ISEL-NEXT: blr
+; ALL-LABEL: select_1_or_0:
+; ALL: # BB#0:
+; ALL-NEXT: clrldi 3, 3, 63
+; ALL-NEXT: blr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
}
define i32 @select_1_or_0_zeroext(i1 zeroext %cond) {
-; ISEL-LABEL: select_1_or_0_zeroext:
-; ISEL: # BB#0:
-; ISEL-NEXT: andi. 3, 3, 1
-; ISEL-NEXT: li 4, 1
-; ISEL-NEXT: li 3, 0
-; ISEL-NEXT: isel 3, 4, 3, 1
-; ISEL-NEXT: blr
-;
-; NO_ISEL-LABEL: select_1_or_0_zeroext:
-; NO_ISEL: # BB#0:
-; NO_ISEL-NEXT: andi. 3, 3, 1
-; NO_ISEL-NEXT: li 4, 1
-; NO_ISEL-NEXT: li 3, 0
-; NO_ISEL-NEXT: bc 12, 1, .LBB4_1
-; NO_ISEL-NEXT: blr
-; NO_ISEL-NEXT: .LBB4_1:
-; NO_ISEL-NEXT: addi 3, 4, 0
-; NO_ISEL-NEXT: blr
+; ALL-LABEL: select_1_or_0_zeroext:
+; ALL: # BB#0:
+; ALL-NEXT: blr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
}
define i32 @select_1_or_0_signext(i1 signext %cond) {
-; ISEL-LABEL: select_1_or_0_signext:
-; ISEL: # BB#0:
-; ISEL-NEXT: andi. 3, 3, 1
-; ISEL-NEXT: li 4, 1
-; ISEL-NEXT: li 3, 0
-; ISEL-NEXT: isel 3, 4, 3, 1
-; ISEL-NEXT: blr
-;
-; NO_ISEL-LABEL: select_1_or_0_signext:
-; NO_ISEL: # BB#0:
-; NO_ISEL-NEXT: andi. 3, 3, 1
-; NO_ISEL-NEXT: li 4, 1
-; NO_ISEL-NEXT: li 3, 0
-; NO_ISEL-NEXT: bc 12, 1, .LBB5_1
-; NO_ISEL-NEXT: blr
-; NO_ISEL-NEXT: .LBB5_1:
-; NO_ISEL-NEXT: addi 3, 4, 0
-; NO_ISEL-NEXT: blr
+; ALL-LABEL: select_1_or_0_signext:
+; ALL: # BB#0:
+; ALL-NEXT: clrldi 3, 3, 63
+; ALL-NEXT: blr
%sel = select i1 %cond, i32 1, i32 0
ret i32 %sel
}
Modified: llvm/trunk/test/CodeGen/X86/select_const.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/select_const.ll?rev=296137&r1=296136&r2=296137&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/select_const.ll (original)
+++ llvm/trunk/test/CodeGen/X86/select_const.ll Fri Feb 24 11:17:33 2017
@@ -108,10 +108,9 @@ define i32 @select_0_or_neg1_signext(i1
define i32 @select_neg1_or_0(i1 %cond) {
; CHECK-LABEL: select_neg1_or_0:
; CHECK: # BB#0:
-; CHECK-NEXT: xorl %ecx, %ecx
-; CHECK-NEXT: testb $1, %dil
-; CHECK-NEXT: movl $-1, %eax
-; CHECK-NEXT: cmovel %ecx, %eax
+; CHECK-NEXT: andl $1, %edi
+; CHECK-NEXT: negl %edi
+; CHECK-NEXT: movl %edi, %eax
; CHECK-NEXT: retq
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
@@ -120,10 +119,8 @@ define i32 @select_neg1_or_0(i1 %cond) {
define i32 @select_neg1_or_0_zeroext(i1 zeroext %cond) {
; CHECK-LABEL: select_neg1_or_0_zeroext:
; CHECK: # BB#0:
-; CHECK-NEXT: xorl %ecx, %ecx
-; CHECK-NEXT: testb %dil, %dil
-; CHECK-NEXT: movl $-1, %eax
-; CHECK-NEXT: cmovel %ecx, %eax
+; CHECK-NEXT: movzbl %dil, %eax
+; CHECK-NEXT: negl %eax
; CHECK-NEXT: retq
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
@@ -132,10 +129,7 @@ define i32 @select_neg1_or_0_zeroext(i1
define i32 @select_neg1_or_0_signext(i1 signext %cond) {
; CHECK-LABEL: select_neg1_or_0_signext:
; CHECK: # BB#0:
-; CHECK-NEXT: xorl %ecx, %ecx
-; CHECK-NEXT: testb $1, %dil
-; CHECK-NEXT: movl $-1, %eax
-; CHECK-NEXT: cmovel %ecx, %eax
+; CHECK-NEXT: movsbl %dil, %eax
; CHECK-NEXT: retq
%sel = select i1 %cond, i32 -1, i32 0
ret i32 %sel
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