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; RUN: llc -march=x86-64 < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-pc-linux-gnu"
; DAGCombiner should fold this code in finite time.
; rdar://8606584
define void @test1() nounwind readnone {
bb.nph:
br label %while.cond
while.cond: ; preds = %while.cond, %bb.nph
%tmp6 = load i32* undef, align 4
%and = or i64 undef, undef
%conv11 = zext i32 undef to i64
%conv14 = zext i32 %tmp6 to i64
%shl15 = shl i64 %conv14, 1
%shl15.masked = and i64 %shl15, 4294967294
%and17 = or i64 %shl15.masked, %conv11
%add = add i64 %and17, 1
%xor = xor i64 %add, %and
%tmp20 = load i64* undef, align 8
%add21 = add i64 %xor, %tmp20
%conv22 = trunc i64 %add21 to i32
store i32 %conv22, i32* undef, align 4
br i1 false, label %while.end, label %while.cond
while.end: ; preds = %while.cond
ret void
}
; DAGCombiner shouldn't fold the sdiv (ashr) away.
; rdar://8636812
; CHECK: test2:
; CHECK: sarl
define i32 @test2() nounwind {
entry:
%i = alloca i32, align 4
%j = alloca i8, align 1
store i32 127, i32* %i, align 4
store i8 0, i8* %j, align 1
%tmp3 = load i32* %i, align 4
%mul = mul nsw i32 %tmp3, 2
%conv4 = trunc i32 %mul to i8
%conv5 = sext i8 %conv4 to i32
%div6 = sdiv i32 %conv5, 2
%conv7 = trunc i32 %div6 to i8
%conv9 = sext i8 %conv7 to i32
%cmp = icmp eq i32 %conv9, -1
br i1 %cmp, label %if.then, label %if.end
if.then: ; preds = %entry
ret i32 0
if.end: ; preds = %entry
call void @abort() noreturn
unreachable
}
declare void @abort() noreturn
declare void @exit(i32) noreturn
; DAG Combiner can't fold this into a load of the 1'th byte.
; PR8757
define i32 @test3(i32 *%P) nounwind ssp {
store volatile i32 128, i32* %P
%tmp4.pre = load i32* %P
%phitmp = trunc i32 %tmp4.pre to i16
%phitmp13 = shl i16 %phitmp, 8
%phitmp14 = ashr i16 %phitmp13, 8
%phitmp15 = lshr i16 %phitmp14, 8
%phitmp16 = zext i16 %phitmp15 to i32
ret i32 %phitmp16
; CHECK: movl $128, (%rdi)
; CHECK-NEXT: movsbl (%rdi), %eax
; CHECK-NEXT: movzbl %ah, %eax
; CHECK-NEXT: ret
}
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