llvm/test/Transforms/LoopIdiom/AMDGPU/popcnt.ll

; RUN: opt -loop-idiom -mtriple=amdgcn-- -S < %s | FileCheck %s

; Mostly copied from x86 version.

;To recognize this pattern:
;int popcount(unsigned long long a) {
;    int c = 0;
;    while (a) {
;        c++;
;        a &= a - 1;
;    }
;    return c;
;}
;

; CHECK-LABEL: @popcount_i64
; CHECK: entry
; CHECK: llvm.ctpop.i64
; CHECK: ret
define i32 @popcount_i64(i64 %a) nounwind uwtable readnone ssp {
entry:
  %tobool3 = icmp eq i64 %a, 0
  br i1 %tobool3, label %while.end, label %while.body

while.body:                                       ; preds = %entry, %while.body
  %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ]
  %a.addr.04 = phi i64 [ %and, %while.body ], [ %a, %entry ]
  %inc = add nsw i32 %c.05, 1
  %sub = add i64 %a.addr.04, -1
  %and = and i64 %sub, %a.addr.04
  %tobool = icmp eq i64 %and, 0
  br i1 %tobool, label %while.end, label %while.body

while.end:                                        ; preds = %while.body, %entry
  %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ]
  ret i32 %c.0.lcssa
}

; CHECK-LABEL: @popcount_i32
; CHECK: entry
; CHECK: llvm.ctpop.i32
; CHECK: ret
define i32 @popcount_i32(i32 %a) nounwind uwtable readnone ssp {
entry:
  %tobool3 = icmp eq i32 %a, 0
  br i1 %tobool3, label %while.end, label %while.body

while.body:                                       ; preds = %entry, %while.body
  %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ]
  %a.addr.04 = phi i32 [ %and, %while.body ], [ %a, %entry ]
  %inc = add nsw i32 %c.05, 1
  %sub = add i32 %a.addr.04, -1
  %and = and i32 %sub, %a.addr.04
  %tobool = icmp eq i32 %and, 0
  br i1 %tobool, label %while.end, label %while.body

while.end:                                        ; preds = %while.body, %entry
  %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ]
  ret i32 %c.0.lcssa
}

; CHECK-LABEL: @popcount_i128
; CHECK: entry
; CHECK: llvm.ctpop.i128
; CHECK: ret
define i32 @popcount_i128(i128 %a) nounwind uwtable readnone ssp {
entry:
  %tobool3 = icmp eq i128 %a, 0
  br i1 %tobool3, label %while.end, label %while.body

while.body:                                       ; preds = %entry, %while.body
  %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ]
  %a.addr.04 = phi i128 [ %and, %while.body ], [ %a, %entry ]
  %inc = add nsw i32 %c.05, 1
  %sub = add i128 %a.addr.04, -1
  %and = and i128 %sub, %a.addr.04
  %tobool = icmp eq i128 %and, 0
  br i1 %tobool, label %while.end, label %while.body

while.end:                                        ; preds = %while.body, %entry
  %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ]
  ret i32 %c.0.lcssa
}

; To recognize this pattern:
;int popcount(unsigned long long a, int mydata1, int mydata2) {
;    int c = 0;
;    while (a) {
;        c++;
;        a &= a - 1;
;        mydata1 *= c;
;        mydata2 *= (int)a;
;    }
;    return c + mydata1 + mydata2;
;}

; CHECK-LABEL: @popcount2
; CHECK: entry
; CHECK: llvm.ctpop.i64
; CHECK: ret
define i32 @popcount2(i64 %a, i32 %mydata1, i32 %mydata2) nounwind uwtable readnone ssp {
entry:
  %tobool9 = icmp eq i64 %a, 0
  br i1 %tobool9, label %while.end, label %while.body

while.body:                                       ; preds = %entry, %while.body
  %c.013 = phi i32 [ %inc, %while.body ], [ 0, %entry ]
  %mydata2.addr.012 = phi i32 [ %mul1, %while.body ], [ %mydata2, %entry ]
  %mydata1.addr.011 = phi i32 [ %mul, %while.body ], [ %mydata1, %entry ]
  %a.addr.010 = phi i64 [ %and, %while.body ], [ %a, %entry ]
  %inc = add nsw i32 %c.013, 1
  %sub = add i64 %a.addr.010, -1
  %and = and i64 %sub, %a.addr.010
  %mul = mul nsw i32 %inc, %mydata1.addr.011
  %conv = trunc i64 %and to i32
  %mul1 = mul nsw i32 %conv, %mydata2.addr.012
  %tobool = icmp eq i64 %and, 0
  br i1 %tobool, label %while.end, label %while.body

while.end:                                        ; preds = %while.body, %entry
  %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ]
  %mydata2.addr.0.lcssa = phi i32 [ %mydata2, %entry ], [ %mul1, %while.body ]
  %mydata1.addr.0.lcssa = phi i32 [ %mydata1, %entry ], [ %mul, %while.body ]
  %add = add i32 %mydata2.addr.0.lcssa, %mydata1.addr.0.lcssa
  %add2 = add i32 %add, %c.0.lcssa
  ret i32 %add2
}