[llvm] 6678db0 - [X86] Enable promotion of i16 popcnt (PR52056)
Dávid Bolvanský via llvm-commits
llvm-commits at lists.llvm.org
Fri Oct 15 06:41:43 PDT 2021
Author: Dávid Bolvanský
Date: 2021-10-15T15:41:37+02:00
New Revision: 6678db00e678e27cc66165ba62d4311f1f7be7b3
URL: https://github.com/llvm/llvm-project/commit/6678db00e678e27cc66165ba62d4311f1f7be7b3
DIFF: https://github.com/llvm/llvm-project/commit/6678db00e678e27cc66165ba62d4311f1f7be7b3.diff
LOG: [X86] Enable promotion of i16 popcnt (PR52056)
Solves https://bugs.llvm.org/show_bug.cgi?id=52056
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111507
Added:
Modified:
llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
llvm/lib/Target/X86/X86ISelLowering.cpp
llvm/test/CodeGen/X86/parity-vec.ll
llvm/test/CodeGen/X86/parity.ll
llvm/test/CodeGen/X86/popcnt.ll
Removed:
################################################################################
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 0824e11574009..f2163373ccaed 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -2662,7 +2662,7 @@ SDValue SelectionDAGLegalize::ExpandPARITY(SDValue Op, const SDLoc &dl) {
// If CTPOP is legal, use it. Otherwise use shifts and xor.
SDValue Result;
- if (TLI.isOperationLegal(ISD::CTPOP, VT)) {
+ if (TLI.isOperationLegalOrPromote(ISD::CTPOP, VT)) {
Result = DAG.getNode(ISD::CTPOP, dl, VT, Op);
} else {
Result = Op;
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index fc6bde29b50fc..2a012666b4719 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -431,6 +431,9 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
setOperationAction(ISD::PARITY, MVT::i64, Custom);
if (Subtarget.hasPOPCNT()) {
setOperationPromotedToType(ISD::CTPOP, MVT::i8, MVT::i32);
+ // popcntw is longer to encode than popcntl and also has a false dependency
+ // on the dest that popcntl hasn't had since Cannon Lake.
+ setOperationPromotedToType(ISD::CTPOP, MVT::i16, MVT::i32);
} else {
setOperationAction(ISD::CTPOP , MVT::i8 , Expand);
setOperationAction(ISD::CTPOP , MVT::i16 , Expand);
diff --git a/llvm/test/CodeGen/X86/parity-vec.ll b/llvm/test/CodeGen/X86/parity-vec.ll
index 0d5f8f4fd0c53..e52a32d261ed2 100644
--- a/llvm/test/CodeGen/X86/parity-vec.ll
+++ b/llvm/test/CodeGen/X86/parity-vec.ll
@@ -18,7 +18,7 @@ define i1 @canonical_parity(<16 x i1> %x) {
; CHECK: # %bb.0:
; CHECK-NEXT: psllw $7, %xmm0
; CHECK-NEXT: pmovmskb %xmm0, %eax
-; CHECK-NEXT: popcntw %ax, %ax
+; CHECK-NEXT: popcntl %eax, %eax
; CHECK-NEXT: testb $1, %al
; CHECK-NEXT: setne %al
; CHECK-NEXT: retq
@@ -33,8 +33,8 @@ define i1 @canonical_parity_noncanonical_pred(<16 x i1> %x) {
; CHECK: # %bb.0:
; CHECK-NEXT: psllw $7, %xmm0
; CHECK-NEXT: pmovmskb %xmm0, %eax
-; CHECK-NEXT: popcntw %ax, %ax
-; CHECK-NEXT: # kill: def $al killed $al killed $ax
+; CHECK-NEXT: popcntl %eax, %eax
+; CHECK-NEXT: # kill: def $al killed $al killed $eax
; CHECK-NEXT: retq
%i1 = bitcast <16 x i1> %x to i16
%i2 = call i16 @llvm.ctpop.i16(i16 %i1)
@@ -62,7 +62,7 @@ define i1 @canonical_nonparity(<16 x i1> %x) {
; CHECK: # %bb.0:
; CHECK-NEXT: psllw $7, %xmm0
; CHECK-NEXT: pmovmskb %xmm0, %eax
-; CHECK-NEXT: popcntw %ax, %ax
+; CHECK-NEXT: popcntl %eax, %eax
; CHECK-NEXT: testb $1, %al
; CHECK-NEXT: sete %al
; CHECK-NEXT: retq
@@ -77,7 +77,7 @@ define i1 @canonical_nonparity_noncanonical_pred(<16 x i1> %x) {
; CHECK: # %bb.0:
; CHECK-NEXT: psllw $7, %xmm0
; CHECK-NEXT: pmovmskb %xmm0, %eax
-; CHECK-NEXT: popcntw %ax, %ax
+; CHECK-NEXT: popcntl %eax, %eax
; CHECK-NEXT: andl $1, %eax
; CHECK-NEXT: xorb $1, %al
; CHECK-NEXT: # kill: def $al killed $al killed $eax
diff --git a/llvm/test/CodeGen/X86/parity.ll b/llvm/test/CodeGen/X86/parity.ll
index ce403c6e8e7fd..5f33db141b542 100644
--- a/llvm/test/CodeGen/X86/parity.ll
+++ b/llvm/test/CodeGen/X86/parity.ll
@@ -59,14 +59,16 @@ define i16 @parity_16(i16 %x) {
;
; X86-POPCNT-LABEL: parity_16:
; X86-POPCNT: # %bb.0:
-; X86-POPCNT-NEXT: popcntw {{[0-9]+}}(%esp), %ax
+; X86-POPCNT-NEXT: movzwl {{[0-9]+}}(%esp), %eax
+; X86-POPCNT-NEXT: popcntl %eax, %eax
; X86-POPCNT-NEXT: andl $1, %eax
; X86-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
; X86-POPCNT-NEXT: retl
;
; X64-POPCNT-LABEL: parity_16:
; X64-POPCNT: # %bb.0:
-; X64-POPCNT-NEXT: popcntw %di, %ax
+; X64-POPCNT-NEXT: movzwl %di, %eax
+; X64-POPCNT-NEXT: popcntl %eax, %eax
; X64-POPCNT-NEXT: andl $1, %eax
; X64-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
; X64-POPCNT-NEXT: retq
@@ -98,14 +100,16 @@ define i16 @parity_16_load(i16* %x) {
; X86-POPCNT-LABEL: parity_16_load:
; X86-POPCNT: # %bb.0:
; X86-POPCNT-NEXT: movl {{[0-9]+}}(%esp), %eax
-; X86-POPCNT-NEXT: popcntw (%eax), %ax
+; X86-POPCNT-NEXT: movzwl (%eax), %eax
+; X86-POPCNT-NEXT: popcntl %eax, %eax
; X86-POPCNT-NEXT: andl $1, %eax
; X86-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
; X86-POPCNT-NEXT: retl
;
; X64-POPCNT-LABEL: parity_16_load:
; X64-POPCNT: # %bb.0:
-; X64-POPCNT-NEXT: popcntw (%rdi), %ax
+; X64-POPCNT-NEXT: movzwl (%rdi), %eax
+; X64-POPCNT-NEXT: popcntl %eax, %eax
; X64-POPCNT-NEXT: andl $1, %eax
; X64-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
; X64-POPCNT-NEXT: retq
@@ -420,7 +424,8 @@ define i16 @parity_16_shift(i16 %0) {
;
; X86-POPCNT-LABEL: parity_16_shift:
; X86-POPCNT: # %bb.0:
-; X86-POPCNT-NEXT: popcntw {{[0-9]+}}(%esp), %ax
+; X86-POPCNT-NEXT: movzwl {{[0-9]+}}(%esp), %eax
+; X86-POPCNT-NEXT: popcntl %eax, %eax
; X86-POPCNT-NEXT: andl $1, %eax
; X86-POPCNT-NEXT: addl %eax, %eax
; X86-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
@@ -428,7 +433,8 @@ define i16 @parity_16_shift(i16 %0) {
;
; X64-POPCNT-LABEL: parity_16_shift:
; X64-POPCNT: # %bb.0:
-; X64-POPCNT-NEXT: popcntw %di, %ax
+; X64-POPCNT-NEXT: movzwl %di, %eax
+; X64-POPCNT-NEXT: popcntl %eax, %eax
; X64-POPCNT-NEXT: andl $1, %eax
; X64-POPCNT-NEXT: addl %eax, %eax
; X64-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
diff --git a/llvm/test/CodeGen/X86/popcnt.ll b/llvm/test/CodeGen/X86/popcnt.ll
index bc24b41ff3d9f..ad0fb4ccfd85b 100644
--- a/llvm/test/CodeGen/X86/popcnt.ll
+++ b/llvm/test/CodeGen/X86/popcnt.ll
@@ -107,12 +107,16 @@ define i16 @cnt16(i16 %x) nounwind readnone {
;
; X86-POPCNT-LABEL: cnt16:
; X86-POPCNT: # %bb.0:
-; X86-POPCNT-NEXT: popcntw {{[0-9]+}}(%esp), %ax
+; X86-POPCNT-NEXT: movzwl {{[0-9]+}}(%esp), %eax
+; X86-POPCNT-NEXT: popcntl %eax, %eax
+; X86-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
; X86-POPCNT-NEXT: retl
;
; X64-POPCNT-LABEL: cnt16:
; X64-POPCNT: # %bb.0:
-; X64-POPCNT-NEXT: popcntw %di, %ax
+; X64-POPCNT-NEXT: movzwl %di, %eax
+; X64-POPCNT-NEXT: popcntl %eax, %eax
+; X64-POPCNT-NEXT: # kill: def $ax killed $ax killed $eax
; X64-POPCNT-NEXT: retq
%cnt = tail call i16 @llvm.ctpop.i16(i16 %x)
ret i16 %cnt
@@ -1564,14 +1568,13 @@ define i32 @popcount_i16_zext(i16 zeroext %x) {
;
; X86-POPCNT-LABEL: popcount_i16_zext:
; X86-POPCNT: # %bb.0:
-; X86-POPCNT-NEXT: popcntw {{[0-9]+}}(%esp), %ax
-; X86-POPCNT-NEXT: movzwl %ax, %eax
+; X86-POPCNT-NEXT: movzwl {{[0-9]+}}(%esp), %eax
+; X86-POPCNT-NEXT: popcntl %eax, %eax
; X86-POPCNT-NEXT: retl
;
; X64-POPCNT-LABEL: popcount_i16_zext:
; X64-POPCNT: # %bb.0:
-; X64-POPCNT-NEXT: popcntw %di, %ax
-; X64-POPCNT-NEXT: movzwl %ax, %eax
+; X64-POPCNT-NEXT: popcntl %edi, %eax
; X64-POPCNT-NEXT: retq
%cnt = tail call i16 @llvm.ctpop.i16(i16 %x)
%z = zext i16 %cnt to i32
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