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Pull in r222292 from upstream llvm trunk (by Weiming Zhao):
[Aarch64] Customer lowering of CTPOP to SIMD should check for NEON
availability
This ensures llvm's AArch64 backend does not emit floating point
instructions if they are disabled.
Introduced here: http://svnweb.freebsd.org/changeset/base/276786
Index: lib/Target/AArch64/AArch64ISelLowering.cpp
===================================================================
--- lib/Target/AArch64/AArch64ISelLowering.cpp
+++ lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -3062,6 +3062,9 @@ SDValue AArch64TargetLowering::LowerCTPOP(SDValue
AttributeSet::FunctionIndex, Attribute::NoImplicitFloat))
return SDValue();
+ if (!Subtarget->hasNEON())
+ return SDValue();
+
// While there is no integer popcount instruction, it can
// be more efficiently lowered to the following sequence that uses
// AdvSIMD registers/instructions as long as the copies to/from
Index: test/CodeGen/AArch64/arm64-popcnt.ll
===================================================================
--- test/CodeGen/AArch64/arm64-popcnt.ll
+++ test/CodeGen/AArch64/arm64-popcnt.ll
@@ -1,4 +1,5 @@
; RUN: llc < %s -march=arm64 -aarch64-neon-syntax=apple | FileCheck %s
+; RUN: llc < %s -march=aarch64 -mattr -neon -aarch64-neon-syntax=apple | FileCheck -check-prefix=CHECK-NONEON %s
define i32 @cnt32_advsimd(i32 %x) nounwind readnone {
%cnt = tail call i32 @llvm.ctpop.i32(i32 %x)
@@ -8,6 +9,13 @@ define i32 @cnt32_advsimd(i32 %x) nounwind readnon
; CHECK: uaddlv.8b h0, v0
; CHECK: fmov w0, s0
; CHECK: ret
+; CHECK-NONEON-LABEL: cnt32_advsimd
+; CHECK-NONEON-NOT: 8b
+; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0x55555555
+; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0x33333333
+; CHECK-NONEON: and w{{[0-9]+}}, w{{[0-9]+}}, #0xf0f0f0f
+; CHECK-NONEON: mul
+
}
define i64 @cnt64_advsimd(i64 %x) nounwind readnone {
@@ -18,6 +26,12 @@ define i64 @cnt64_advsimd(i64 %x) nounwind readnon
; CHECK: uaddlv.8b h0, v0
; CHECK: fmov w0, s0
; CHECK: ret
+; CHECK-NONEON-LABEL: cnt64_advsimd
+; CHECK-NONEON-NOT: 8b
+; CHECK-NONEON: and x{{[0-9]+}}, x{{[0-9]+}}, #0x5555555555555555
+; CHECK-NONEON: and x{{[0-9]+}}, x{{[0-9]+}}, #0x3333333333333333
+; CHECK-NONEON: and x{{[0-9]+}}, x{{[0-9]+}}, #0xf0f0f0f0f0f0f0f
+; CHECK-NONEON: mul
}
; Do not use AdvSIMD when -mno-implicit-float is specified.
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