llvm/test/CodeGen/ARM/cttz.ll
Logan Chien af3e4a2f2f ARM: Fix cttz expansion on vector types.
The 64/128-bit vector types are legal if NEON instructions are
available.  However, there was no matching patterns for @llvm.cttz.*()
intrinsics and result in fatal error.

This commit fixes the problem by lowering cttz to:
a. ctpop((x & -x) - 1)
b. width - ctlz(x & -x) - 1


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242037 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 15:37:30 +00:00

91 lines
2.0 KiB
LLVM

; RUN: llc < %s -mtriple arm-eabi -mattr=+v6t2 | FileCheck %s
; RUN: llc < %s -mtriple arm-eabi -mattr=+v6t2 -mattr=+neon | FileCheck %s
; This test checks the @llvm.cttz.* intrinsics for integers.
declare i8 @llvm.cttz.i8(i8, i1)
declare i16 @llvm.cttz.i16(i16, i1)
declare i32 @llvm.cttz.i32(i32, i1)
declare i64 @llvm.cttz.i64(i64, i1)
;------------------------------------------------------------------------------
define i8 @test_i8(i8 %a) {
; CHECK-LABEL: test_i8:
; CHECK: orr [[REG:r[0-9]+]], [[REG]], #256
; CHECK: rbit
; CHECK: clz
%tmp = call i8 @llvm.cttz.i8(i8 %a, i1 false)
ret i8 %tmp
}
define i16 @test_i16(i16 %a) {
; CHECK-LABEL: test_i16:
; CHECK: orr [[REG:r[0-9]+]], [[REG]], #65536
; CHECK: rbit
; CHECK: clz
%tmp = call i16 @llvm.cttz.i16(i16 %a, i1 false)
ret i16 %tmp
}
define i32 @test_i32(i32 %a) {
; CHECK-LABEL: test_i32:
; CHECK: rbit
; CHECK: clz
%tmp = call i32 @llvm.cttz.i32(i32 %a, i1 false)
ret i32 %tmp
}
define i64 @test_i64(i64 %a) {
; CHECK-LABEL: test_i64:
; CHECK: rbit
; CHECK: rbit
; CHECK: cmp
; CHECK: clz
; CHECK: add
; CHECK: clzne
%tmp = call i64 @llvm.cttz.i64(i64 %a, i1 false)
ret i64 %tmp
}
;------------------------------------------------------------------------------
define i8 @test_i8_zero_undef(i8 %a) {
; CHECK-LABEL: test_i8_zero_undef:
; CHECK-NOT: orr
; CHECK: rbit
; CHECK: clz
%tmp = call i8 @llvm.cttz.i8(i8 %a, i1 true)
ret i8 %tmp
}
define i16 @test_i16_zero_undef(i16 %a) {
; CHECK-LABEL: test_i16_zero_undef:
; CHECK-NOT: orr
; CHECK: rbit
; CHECK: clz
%tmp = call i16 @llvm.cttz.i16(i16 %a, i1 true)
ret i16 %tmp
}
define i32 @test_i32_zero_undef(i32 %a) {
; CHECK-LABEL: test_i32_zero_undef:
; CHECK: rbit
; CHECK: clz
%tmp = call i32 @llvm.cttz.i32(i32 %a, i1 true)
ret i32 %tmp
}
define i64 @test_i64_zero_undef(i64 %a) {
; CHECK-LABEL: test_i64_zero_undef:
; CHECK: rbit
; CHECK: rbit
; CHECK: cmp
; CHECK: clz
; CHECK: add
; CHECK: clzne
%tmp = call i64 @llvm.cttz.i64(i64 %a, i1 true)
ret i64 %tmp
}