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|
; RUN: llc -mtriple=arm-eabi -arm-atomic-cfg-tidy=0 %s -o - | FileCheck -check-prefix=ARM %s
; RUN: llc -mtriple=thumb-eabi -arm-atomic-cfg-tidy=0 %s -o - | FileCheck -check-prefix=THUMB %s
; RUN: llc -mtriple=thumb-eabi -arm-atomic-cfg-tidy=0 -mcpu=arm1156t2-s -mattr=+thumb2 %s -o - | FileCheck -check-prefix=T2 %s
; RUN: llc -mtriple=thumbv8-eabi -arm-atomic-cfg-tidy=0 %s -o - | FileCheck -check-prefix=V8 %s
; FIXME: The -mtriple=thumb test doesn't change if -disable-peephole is specified.
%struct.Foo = type { i8* }
; ARM-LABEL: foo:
; THUMB-LABEL: foo:
; T2-LABEL: foo:
define %struct.Foo* @foo(%struct.Foo* %this, i32 %acc) nounwind readonly align 2 {
entry:
%scevgep = getelementptr %struct.Foo, %struct.Foo* %this, i32 1
br label %tailrecurse
tailrecurse: ; preds = %sw.bb, %entry
%lsr.iv2 = phi %struct.Foo* [ %scevgep3, %sw.bb ], [ %scevgep, %entry ]
%lsr.iv = phi i32 [ %lsr.iv.next, %sw.bb ], [ 1, %entry ]
%acc.tr = phi i32 [ %or, %sw.bb ], [ %acc, %entry ]
%lsr.iv24 = bitcast %struct.Foo* %lsr.iv2 to i8**
%scevgep5 = getelementptr i8*, i8** %lsr.iv24, i32 -1
%tmp2 = load i8*, i8** %scevgep5
%0 = ptrtoint i8* %tmp2 to i32
; ARM: ands {{r[0-9]+}}, {{r[0-9]+}}, #3
; ARM-NEXT: beq
; THUMB: movs r[[R0:[0-9]+]], #3
; THUMB-NEXT: ands r[[R0]], r
; THUMB-NEXT: beq
; T2: ands {{r[0-9]+}}, {{r[0-9]+}}, #3
; T2-NEXT: beq
%and = and i32 %0, 3
%tst = icmp eq i32 %and, 0
br i1 %tst, label %sw.bb, label %tailrecurse.switch
tailrecurse.switch: ; preds = %tailrecurse
; V8-LABEL: %tailrecurse.switch
; V8: cmp
; V8-NEXT: beq
; V8-NEXT: %tailrecurse.switch
; V8: cmp
; V8-NEXT: beq
; V8-NEXT: %tailrecurse.switch
; V8: cmp
; V8-NEXT: bne
; V8-NEXT: %sw.bb
switch i32 %and, label %sw.epilog [
i32 1, label %sw.bb
i32 3, label %sw.bb6
i32 2, label %sw.bb8
], !prof !1
sw.bb: ; preds = %tailrecurse.switch, %tailrecurse
%shl = shl i32 %acc.tr, 1
%or = or i32 %and, %shl
%lsr.iv.next = add i32 %lsr.iv, 1
%scevgep3 = getelementptr %struct.Foo, %struct.Foo* %lsr.iv2, i32 1
br label %tailrecurse
sw.bb6: ; preds = %tailrecurse.switch
ret %struct.Foo* %lsr.iv2
sw.bb8: ; preds = %tailrecurse.switch
%tmp1 = add i32 %acc.tr, %lsr.iv
%add.ptr11 = getelementptr inbounds %struct.Foo, %struct.Foo* %this, i32 %tmp1
ret %struct.Foo* %add.ptr11
sw.epilog: ; preds = %tailrecurse.switch
ret %struct.Foo* undef
}
; Another test that exercises the AND/TST peephole optimization and also
; generates a predicated ANDS instruction. Check that the predicate is printed
; after the "S" modifier on the instruction.
%struct.S = type { i8* (i8*)*, [1 x i8] }
; ARM-LABEL: bar:
; THUMB-LABEL: bar:
; T2-LABEL: bar:
; V8-LABEL: bar:
define internal zeroext i8 @bar(%struct.S* %x, %struct.S* nocapture %y) nounwind readonly {
entry:
%0 = getelementptr inbounds %struct.S, %struct.S* %x, i32 0, i32 1, i32 0
%1 = load i8, i8* %0, align 1
%2 = zext i8 %1 to i32
; ARM: ands
; THUMB: ands
; T2: ands
; V8: ands
; V8-NEXT: beq
%3 = and i32 %2, 112
%4 = icmp eq i32 %3, 0
br i1 %4, label %return, label %bb
bb: ; preds = %entry
; V8-NEXT: %bb
%5 = getelementptr inbounds %struct.S, %struct.S* %y, i32 0, i32 1, i32 0
%6 = load i8, i8* %5, align 1
%7 = zext i8 %6 to i32
; ARM: andsne
; THUMB: ands
; T2: andsne
; V8: ands
; V8-NEXT: beq
%8 = and i32 %7, 112
%9 = icmp eq i32 %8, 0
br i1 %9, label %return, label %bb2
bb2: ; preds = %bb
; V8-NEXT: %bb2
; V8-NEXT: cmp
; V8-NEXT: it ne
; V8-NEXT: cmpne
; V8-NEXT: bne
%10 = icmp eq i32 %3, 16
%11 = icmp eq i32 %8, 16
%or.cond = or i1 %10, %11
br i1 %or.cond, label %bb4, label %return
bb4: ; preds = %bb2
%12 = ptrtoint %struct.S* %x to i32
%phitmp = trunc i32 %12 to i8
ret i8 %phitmp
return: ; preds = %bb2, %bb, %entry
ret i8 1
}
; We were looking through multiple COPY instructions to find an AND we might
; fold into a TST, but in doing so we changed the register being tested allowing
; folding of unrelated tests (in this case, a TST against r1 was eliminated in
; favour of an AND of r0).
define i32 @test_tst_assessment(i32 %a, i32 %b) {
; ARM-LABEL: test_tst_assessment:
; ARM: @ %bb.0:
; ARM-NEXT: and r0, r0, #1
; ARM-NEXT: tst r1, #1
; ARM-NEXT: subne r0, r0, #1
; ARM-NEXT: mov pc, lr
;
; THUMB-LABEL: test_tst_assessment:
; THUMB: @ %bb.0:
; THUMB-NEXT: movs r2, r0
; THUMB-NEXT: movs r0, #1
; THUMB-NEXT: ands r0, r2
; THUMB-NEXT: lsls r1, r1, #31
; THUMB-NEXT: beq .LBB2_2
; THUMB-NEXT: @ %bb.1:
; THUMB-NEXT: subs r0, r0, #1
; THUMB-NEXT: .LBB2_2:
; THUMB-NEXT: bx lr
;
; T2-LABEL: test_tst_assessment:
; T2: @ %bb.0:
; T2-NEXT: and r0, r0, #1
; T2-NEXT: lsls r1, r1, #31
; T2-NEXT: it ne
; T2-NEXT: subne r0, #1
; T2-NEXT: bx lr
;
; V8-LABEL: test_tst_assessment:
; V8: @ %bb.0:
; V8-NEXT: and r2, r0, #1
; V8-NEXT: subs r0, r2, #1
; V8-NEXT: lsls r1, r1, #31
; V8-NEXT: it eq
; V8-NEXT: moveq r0, r2
; V8-NEXT: bx lr
%and1 = and i32 %a, 1
%sub = sub i32 %and1, 1
%and2 = and i32 %b, 1
%cmp = icmp eq i32 %and2, 0
%sel = select i1 %cmp, i32 %and1, i32 %sub
ret i32 %sel
}
!1 = !{!"branch_weights", i32 1, i32 1, i32 3, i32 2 }
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