reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
; RUN: llc < %s -march=nvptx -mcpu=sm_20 -verify-machineinstrs | FileCheck %s

target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v16:16:16-v32:32:32-v64:64:64-v128:128:128-n16:32:64"

declare i16 @llvm.ctlz.i16(i16, i1) readnone
declare i32 @llvm.ctlz.i32(i32, i1) readnone
declare i64 @llvm.ctlz.i64(i64, i1) readnone

; There should be no difference between llvm.ctlz.i32(%a, true) and
; llvm.ctlz.i32(%a, false), as ptx's clz(0) is defined to return 0.

; CHECK-LABEL: myctlz(
define i32 @myctlz(i32 %a) {
; CHECK: ld.param.
; CHECK-NEXT: clz.b32
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i32 @llvm.ctlz.i32(i32 %a, i1 false) readnone
  ret i32 %val
}
; CHECK-LABEL: myctlz_2(
define i32 @myctlz_2(i32 %a) {
; CHECK: ld.param.
; CHECK-NEXT: clz.b32
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i32 @llvm.ctlz.i32(i32 %a, i1 true) readnone
  ret i32 %val
}

; PTX's clz.b64 returns a 32-bit value, but LLVM's intrinsic returns a 64-bit
; value, so here we have to zero-extend it.
; CHECK-LABEL: myctlz64(
define i64 @myctlz64(i64 %a) {
; CHECK: ld.param.
; CHECK-NEXT: clz.b64
; CHECK-NEXT: cvt.u64.u32
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i64 @llvm.ctlz.i64(i64 %a, i1 false) readnone
  ret i64 %val
}
; CHECK-LABEL: myctlz64_2(
define i64 @myctlz64_2(i64 %a) {
; CHECK: ld.param.
; CHECK-NEXT: clz.b64
; CHECK-NEXT: cvt.u64.u32
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i64 @llvm.ctlz.i64(i64 %a, i1 true) readnone
  ret i64 %val
}

; Here we truncate the 64-bit value of LLVM's ctlz intrinsic to 32 bits, the
; natural return width of ptx's clz.b64 instruction.  No conversions should be
; necessary in the PTX.
; CHECK-LABEL: myctlz64_as_32(
define i32 @myctlz64_as_32(i64 %a) {
; CHECK: ld.param.
; CHECK-NEXT: clz.b64
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i64 @llvm.ctlz.i64(i64 %a, i1 false) readnone
  %trunc = trunc i64 %val to i32
  ret i32 %trunc
}
; CHECK-LABEL: myctlz64_as_32_2(
define i32 @myctlz64_as_32_2(i64 %a) {
; CHECK: ld.param.
; CHECK-NEXT: clz.b64
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i64 @llvm.ctlz.i64(i64 %a, i1 false) readnone
  %trunc = trunc i64 %val to i32
  ret i32 %trunc
}

; ctlz.i16 is implemented by extending the input to i32, computing the result,
; and then truncating the result back down to i16.  But the NVPTX ABI
; zero-extends i16 return values to i32, so the final truncation doesn't appear
; in this function.
; CHECK-LABEL: myctlz_ret16(
define i16 @myctlz_ret16(i16 %a) {
; CHECK: ld.param.
; CHECK-NEXT: cvt.u32.u16
; CHECK-NEXT: clz.b32
; CHECK-NEXT: sub.
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i16 @llvm.ctlz.i16(i16 %a, i1 false) readnone
  ret i16 %val
}
; CHECK-LABEL: myctlz_ret16_2(
define i16 @myctlz_ret16_2(i16 %a) {
; CHECK: ld.param.
; CHECK-NEXT: cvt.u32.u16
; CHECK-NEXT: clz.b32
; CHECK-NEXT: sub.
; CHECK-NEXT: st.param.
; CHECK-NEXT: ret;
  %val = call i16 @llvm.ctlz.i16(i16 %a, i1 true) readnone
  ret i16 %val
}

; Here we store the result of ctlz.16 into an i16 pointer, so the trunc should
; remain.
; CHECK-LABEL: myctlz_store16(
define void @myctlz_store16(i16 %a, i16* %b) {
; CHECK: ld.param.
; CHECK-NEXT: cvt.u32.u16
; CHECK-NEXT: clz.b32
; CHECK-DAG: cvt.u16.u32
; CHECK-DAG: sub.
; CHECK: st.{{[a-z]}}16
; CHECK: ret;
  %val = call i16 @llvm.ctlz.i16(i16 %a, i1 false) readnone
  store i16 %val, i16* %b
  ret void
}
; CHECK-LABEL: myctlz_store16_2(
define void @myctlz_store16_2(i16 %a, i16* %b) {
; CHECK: ld.param.
; CHECK-NEXT: cvt.u32.u16
; CHECK-NEXT: clz.b32
; CHECK-DAG: cvt.u16.u32
; CHECK-DAG: sub.
; CHECK: st.{{[a-z]}}16
; CHECK: ret;
  %val = call i16 @llvm.ctlz.i16(i16 %a, i1 false) readnone
  store i16 %val, i16* %b
  ret void
}