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|
; RUN: llc < %s -march=x86 -mcpu=pentiumpro -verify-machineinstrs | FileCheck %s
define i32 @f(i32 %X) {
entry:
; CHECK: f:
; CHECK: jns
%tmp1 = add i32 %X, 1 ; <i32> [#uses=1]
%tmp = icmp slt i32 %tmp1, 0 ; <i1> [#uses=1]
br i1 %tmp, label %cond_true, label %cond_next
cond_true: ; preds = %entry
%tmp2 = tail call i32 (...)* @bar( ) ; <i32> [#uses=0]
br label %cond_next
cond_next: ; preds = %cond_true, %entry
%tmp3 = tail call i32 (...)* @baz( ) ; <i32> [#uses=0]
ret i32 undef
}
declare i32 @bar(...)
declare i32 @baz(...)
; rdar://10633221
; rdar://11355268
define i32 @g(i32 %a, i32 %b) nounwind {
entry:
; CHECK: g:
; CHECK-NOT: test
; CHECK: cmovs
%sub = sub nsw i32 %a, %b
%cmp = icmp sgt i32 %sub, 0
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
; rdar://10734411
define i32 @h(i32 %a, i32 %b) nounwind {
entry:
; CHECK: h:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp slt i32 %b, %a
%sub = sub nsw i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @i(i32 %a, i32 %b) nounwind {
entry:
; CHECK: i:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp sgt i32 %a, %b
%sub = sub nsw i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @j(i32 %a, i32 %b) nounwind {
entry:
; CHECK: j:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp ugt i32 %a, %b
%sub = sub i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @k(i32 %a, i32 %b) nounwind {
entry:
; CHECK: k:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp ult i32 %b, %a
%sub = sub i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
; redundant cmp instruction
define i32 @l(i32 %a, i32 %b) nounwind {
entry:
; CHECK: l:
; CHECK-NOT: cmp
%cmp = icmp slt i32 %b, %a
%sub = sub nsw i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 %a
ret i32 %cond
}
define i32 @m(i32 %a, i32 %b) nounwind {
entry:
; CHECK: m:
; CHECK-NOT: cmp
%cmp = icmp sgt i32 %a, %b
%sub = sub nsw i32 %a, %b
%cond = select i1 %cmp, i32 %b, i32 %sub
ret i32 %cond
}
; If EFLAGS is live-out, we can't remove cmp if there exists
; a swapped sub.
define i32 @l2(i32 %a, i32 %b) nounwind {
entry:
; CHECK: l2:
; CHECK: cmp
%cmp = icmp eq i32 %b, %a
%sub = sub nsw i32 %a, %b
br i1 %cmp, label %if.then, label %if.else
if.then:
%cmp2 = icmp sgt i32 %b, %a
%sel = select i1 %cmp2, i32 %sub, i32 %a
ret i32 %sel
if.else:
ret i32 %sub
}
define i32 @l3(i32 %a, i32 %b) nounwind {
entry:
; CHECK: l3:
; CHECK: sub
; CHECK-NOT: cmp
; CHECK: jge
%cmp = icmp sgt i32 %b, %a
%sub = sub nsw i32 %a, %b
br i1 %cmp, label %if.then, label %if.else
if.then:
ret i32 %sub
if.else:
%add = add nsw i32 %sub, 1
ret i32 %add
}
; rdar://11830760
; When Movr0 is between sub and cmp, we need to move "Movr0" before sub.
define i32 @l4(i32 %a, i32 %b) nounwind {
entry:
; CHECK: l4:
; CHECK: xor
; CHECK: sub
; CHECK-NOT: cmp
%cmp = icmp sgt i32 %b, %a
%sub = sub i32 %a, %b
%.sub = select i1 %cmp, i32 0, i32 %sub
ret i32 %.sub
}
; rdar://11540023
define i32 @n(i32 %x, i32 %y) nounwind {
entry:
; CHECK: n:
; CHECK-NOT: sub
; CHECK: cmp
%sub = sub nsw i32 %x, %y
%cmp = icmp slt i32 %sub, 0
%y.x = select i1 %cmp, i32 %y, i32 %x
ret i32 %y.x
}
; PR://13046
define void @o() nounwind uwtable {
entry:
%0 = load i16* undef, align 2
br i1 undef, label %if.then.i, label %if.end.i
if.then.i: ; preds = %entry
unreachable
if.end.i: ; preds = %entry
br i1 undef, label %sw.bb, label %sw.default
sw.bb: ; preds = %if.end.i
br i1 undef, label %if.then44, label %if.end29
if.end29: ; preds = %sw.bb
; CHECK: o:
; CHECK: cmp
%1 = urem i16 %0, 10
%cmp25 = icmp eq i16 %1, 0
%. = select i1 %cmp25, i16 2, i16 0
br i1 %cmp25, label %if.then44, label %sw.default
sw.default: ; preds = %if.end29, %if.end.i
br i1 undef, label %if.then.i96, label %if.else.i97
if.then.i96: ; preds = %sw.default
unreachable
if.else.i97: ; preds = %sw.default
unreachable
if.then44: ; preds = %if.end29, %sw.bb
%aModeRefSel.1.ph = phi i16 [ %., %if.end29 ], [ 3, %sw.bb ]
br i1 undef, label %if.then.i103, label %if.else.i104
if.then.i103: ; preds = %if.then44
unreachable
if.else.i104: ; preds = %if.then44
ret void
}
; rdar://11855129
define i32 @p(i32 %a, i32 %b) nounwind {
entry:
; CHECK: p:
; CHECK-NOT: test
; CHECK: cmovs
%add = add nsw i32 %b, %a
%cmp = icmp sgt i32 %add, 0
%add. = select i1 %cmp, i32 %add, i32 0
ret i32 %add.
}
; PR13475
; If we have sub a, b and cmp b, a and the result of cmp is used
; by sbb, we should not optimize cmp away.
define i32 @q(i32 %j.4, i32 %w, i32 %el) {
; CHECK: q:
; CHECK: cmp
; CHECK-NEXT: sbb
%tmp532 = add i32 %j.4, %w
%tmp533 = icmp ugt i32 %tmp532, %el
%tmp534 = icmp ult i32 %w, %el
%or.cond = and i1 %tmp533, %tmp534
%tmp535 = sub i32 %el, %w
%j.5 = select i1 %or.cond, i32 %tmp535, i32 %j.4
ret i32 %j.5
}
; rdar://11873276
define i8* @r(i8* %base, i32* nocapture %offset, i32 %size) nounwind {
entry:
; CHECK: r:
; CHECK: sub
; CHECK-NOT: cmp
; CHECK: j
; CHECK-NOT: sub
; CHECK: ret
%0 = load i32* %offset, align 8
%cmp = icmp slt i32 %0, %size
br i1 %cmp, label %return, label %if.end
if.end:
%sub = sub nsw i32 %0, %size
store i32 %sub, i32* %offset, align 8
%add.ptr = getelementptr inbounds i8* %base, i32 %sub
br label %return
return:
%retval.0 = phi i8* [ %add.ptr, %if.end ], [ null, %entry ]
ret i8* %retval.0
}
; Test optimizations of dec/inc.
define i32 @dec(i32 %a) nounwind {
entry:
; CHECK: dec:
; CHECK: decl
; CHECK-NOT: test
; CHECK: cmovsl
%sub = sub nsw i32 %a, 1
%cmp = icmp sgt i32 %sub, 0
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @inc(i32 %a) nounwind {
entry:
; CHECK: inc:
; CHECK: incl
; CHECK-NOT: test
; CHECK: cmovsl
%add = add nsw i32 %a, 1
%cmp = icmp sgt i32 %add, 0
%cond = select i1 %cmp, i32 %add, i32 0
ret i32 %cond
}
; PR13966
@b = common global i32 0, align 4
@a = common global i32 0, align 4
define i32 @test1(i32 %p1) nounwind uwtable {
entry:
; CHECK: test1:
; CHECK: testb
; CHECK: j
; CHECK: ret
%0 = load i32* @b, align 4
%cmp = icmp ult i32 %0, %p1
%conv = zext i1 %cmp to i32
%1 = load i32* @a, align 4
%and = and i32 %conv, %1
%conv1 = trunc i32 %and to i8
%2 = urem i8 %conv1, 3
%tobool = icmp eq i8 %2, 0
br i1 %tobool, label %if.end, label %if.then
if.then:
%dec = add nsw i32 %1, -1
store i32 %dec, i32* @a, align 4
br label %if.end
if.end:
ret i32 undef
}
|
