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      1 ; Test 8-bit compare and swap.
      2 ;
      3 ; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s -check-prefix=CHECK-MAIN
      4 ; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s -check-prefix=CHECK-SHIFT
      5 
      6 ; Check compare and swap with a variable.
      7 ; - CHECK is for the main loop.
      8 ; - CHECK-SHIFT makes sure that the negated shift count used by the second
      9 ;   RLL is set up correctly.  The negation is independent of the NILL and L
     10 ;   tested in CHECK.  CHECK-SHIFT also checks that %r3 is not modified before
     11 ;   being used in the RISBG (in contrast to things like atomic addition,
     12 ;   which shift %r3 left so that %b is at the high end of the word).
     13 define i8 @f1(i8 %dummy, i8 *%src, i8 %cmp, i8 %swap) {
     14 ; CHECK-MAIN-LABEL: f1:
     15 ; CHECK-MAIN: risbg [[RISBG:%r[1-9]+]], %r3, 0, 189, 0{{$}}
     16 ; CHECK-MAIN: sll %r3, 3
     17 ; CHECK-MAIN: l [[OLD:%r[0-9]+]], 0([[RISBG]])
     18 ; CHECK-MAIN: [[LOOP:\.[^ ]*]]:
     19 ; CHECK-MAIN: rll %r2, [[OLD]], 8(%r3)
     20 ; CHECK-MAIN: risbg %r4, %r2, 32, 55, 0
     21 ; CHECK-MAIN: crjlh %r2, %r4, [[EXIT:\.[^ ]*]]
     22 ; CHECK-MAIN: risbg %r5, %r2, 32, 55, 0
     23 ; CHECK-MAIN: rll [[NEW:%r[0-9]+]], %r5, -8({{%r[1-9]+}})
     24 ; CHECK-MAIN: cs [[OLD]], [[NEW]], 0([[RISBG]])
     25 ; CHECK-MAIN: jl [[LOOP]]
     26 ; CHECK-MAIN: [[EXIT]]:
     27 ; CHECK-MAIN-NOT: %r2
     28 ; CHECK-MAIN: br %r14
     29 ;
     30 ; CHECK-SHIFT-LABEL: f1:
     31 ; CHECK-SHIFT: sll [[SHIFT:%r[1-9]+]], 3
     32 ; CHECK-SHIFT: lcr [[NEGSHIFT:%r[1-9]+]], [[SHIFT]]
     33 ; CHECK-SHIFT: rll
     34 ; CHECK-SHIFT: rll {{%r[0-9]+}}, %r5, -8([[NEGSHIFT]])
     35   %pair = cmpxchg i8 *%src, i8 %cmp, i8 %swap seq_cst seq_cst
     36   %res = extractvalue { i8, i1 } %pair, 0
     37   ret i8 %res
     38 }
     39 
     40 ; Check compare and swap with constants.  We should force the constants into
     41 ; registers and use the sequence above.
     42 define i8 @f2(i8 *%src) {
     43 ; CHECK-LABEL: f2:
     44 ; CHECK: lhi [[CMP:%r[0-9]+]], 42
     45 ; CHECK: risbg [[CMP]], {{%r[0-9]+}}, 32, 55, 0
     46 ; CHECK: risbg
     47 ; CHECK: br %r14
     48 ;
     49 ; CHECK-SHIFT-LABEL: f2:
     50 ; CHECK-SHIFT: lhi [[SWAP:%r[0-9]+]], 88
     51 ; CHECK-SHIFT: risbg
     52 ; CHECK-SHIFT: risbg [[SWAP]], {{%r[0-9]+}}, 32, 55, 0
     53 ; CHECK-SHIFT: br %r14
     54   %pair = cmpxchg i8 *%src, i8 42, i8 88 seq_cst seq_cst
     55   %res = extractvalue { i8, i1 } %pair, 0
     56   ret i8 %res
     57 }
     58