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; RUN: opt -S -basic-aa -gvn < %s | FileCheck %s
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32"
target triple = "i386-apple-darwin11.0.0"
@sortlist = external global [5001 x i32], align 4
define void @Bubble() nounwind noinline {
; CHECK: entry:
; CHECK-NEXT: %tmp7.pre = load i32
entry:
br label %while.body5
; CHECK: while.body5:
; CHECK: %tmp7 = phi i32
; CHECK-NOT: %tmp7 = load i32
while.body5:
%indvar = phi i32 [ 0, %entry ], [ %tmp6, %if.end ]
%tmp5 = add i32 %indvar, 2
%arrayidx9 = getelementptr [5001 x i32], [5001 x i32]* @sortlist, i32 0, i32 %tmp5
%tmp6 = add i32 %indvar, 1
%arrayidx = getelementptr [5001 x i32], [5001 x i32]* @sortlist, i32 0, i32 %tmp6
%tmp7 = load i32, i32* %arrayidx, align 4
%tmp10 = load i32, i32* %arrayidx9, align 4
%cmp11 = icmp sgt i32 %tmp7, %tmp10
br i1 %cmp11, label %if.then, label %if.end
; CHECK: if.then:
if.then:
store i32 %tmp10, i32* %arrayidx, align 4
store i32 %tmp7, i32* %arrayidx9, align 4
br label %if.end
if.end:
%exitcond = icmp eq i32 %tmp6, 100
br i1 %exitcond, label %while.end.loopexit, label %while.body5
while.end.loopexit:
ret void
}
declare void @hold(i32) readonly
declare void @clobber()
; This is a classic LICM case
define i32 @test1(i1 %cnd, i32* %p) {
; CHECK-LABEL: @test1
entry:
; CHECK-LABEL: entry
; CHECK-NEXT: %v1.pre = load i32, i32* %p
br label %header
header:
; CHECK-LABEL: header
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br label %header
}
; Slightly more complicated case to highlight that MemoryDependenceAnalysis
; can compute availability for internal control flow. In this case, because
; the value is fully available across the backedge, we only need to establish
; anticipation for the preheader block (which is trivial in this case.)
define i32 @test2(i1 %cnd, i32* %p) {
; CHECK-LABEL: @test2
entry:
; CHECK-LABEL: entry
; CHECK-NEXT: %v1.pre = load i32, i32* %p
br label %header
header:
; CHECK-LABEL: header
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br i1 %cnd, label %bb1, label %bb2
bb1:
br label %merge
bb2:
br label %merge
merge:
br label %header
}
; TODO: at the moment, our anticipation check does not handle anything
; other than straight-line unconditional fallthrough. This particular
; case could be solved through either a backwards anticipation walk or
; use of the "safe to speculate" status (if we annotate the param)
define i32 @test3(i1 %cnd, i32* %p) {
entry:
; CHECK-LABEL: @test3
; CHECK-LABEL: entry
br label %header
header:
br i1 %cnd, label %bb1, label %bb2
bb1:
br label %merge
bb2:
br label %merge
merge:
; CHECK-LABEL: merge
; CHECK: load i32, i32* %p
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br label %header
}
; Highlight that we can PRE into a latch block when there are multiple
; latches only one of which clobbers an otherwise invariant value.
define i32 @test4(i1 %cnd, i32* %p) {
; CHECK-LABEL: @test4
entry:
; CHECK-LABEL: entry
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br label %header
header:
; CHECK-LABEL: header
%v2 = load i32, i32* %p
call void @hold(i32 %v2)
br i1 %cnd, label %bb1, label %bb2
bb1:
br label %header
bb2:
; CHECK-LABEL: bb2
; CHECK: call void @clobber()
; CHECK-NEXT: %v2.pre = load i32, i32* %p
; CHECK-NEXT: br label %header
call void @clobber()
br label %header
}
; Highlight the fact that we can PRE into a single clobbering latch block
; even in loop simplify form (though multiple applications of the same
; transformation).
define i32 @test5(i1 %cnd, i32* %p) {
; CHECK-LABEL: @test5
entry:
; CHECK-LABEL: entry
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br label %header
header:
; CHECK-LABEL: header
%v2 = load i32, i32* %p
call void @hold(i32 %v2)
br i1 %cnd, label %bb1, label %bb2
bb1:
br label %merge
bb2:
; CHECK-LABEL: bb2
; CHECK: call void @clobber()
; CHECK-NEXT: %v2.pre.pre = load i32, i32* %p
; CHECK-NEXT: br label %merge
call void @clobber()
br label %merge
merge:
br label %header
}
declare void @llvm.experimental.guard(i1 %cnd, ...)
; These two tests highlight speculation safety when we can not establish
; anticipation (since the original load might actually not execcute)
define i32 @test6a(i1 %cnd, i32* %p) {
entry:
; CHECK-LABEL: @test6a
br label %header
header:
; CHECK-LABEL: header
; CHECK: load i32, i32* %p
call void (i1, ...) @llvm.experimental.guard(i1 %cnd) ["deopt"()]
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br label %header
}
define i32 @test6b(i1 %cnd, i32* dereferenceable(8) align 4 %p) {
entry:
; CHECK-LABEL: @test6b
; CHECK: load i32, i32* %p
br label %header
header:
; CHECK-LABEL: header
call void (i1, ...) @llvm.experimental.guard(i1 %cnd) ["deopt"()]
%v1 = load i32, i32* %p
call void @hold(i32 %v1)
br label %header
}
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