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1; RUN: llc < %s -march=x86-64 | grep lea | count 12
2
3; This testcase was written to demonstrate an instruction-selection problem,
4; however it also happens to expose a limitation in the DAGCombiner's
5; expression reassociation which causes it to miss opportunities for
6; constant folding due to the intermediate adds having multiple uses.
7; The Reassociate pass has similar limitations. If these limitations are
8; fixed, the test commands above will need to be updated to expect fewer
9; lea instructions.
10
11@g0 = weak global [1000 x i32] zeroinitializer, align 32		; <[1000 x i32]*> [#uses=8]
12@g1 = weak global [1000 x i32] zeroinitializer, align 32		; <[1000 x i32]*> [#uses=7]
13
14define void @foo() {
15entry:
16	%tmp4 = load i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 0)		; <i32> [#uses=1]
17	%tmp8 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 0)		; <i32> [#uses=1]
18	%tmp9 = add i32 %tmp4, 1		; <i32> [#uses=1]
19	%tmp10 = add i32 %tmp9, %tmp8		; <i32> [#uses=2]
20	store i32 %tmp10, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 1)
21	%tmp8.1 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 1)		; <i32> [#uses=1]
22	%tmp9.1 = add i32 %tmp10, 1		; <i32> [#uses=1]
23	%tmp10.1 = add i32 %tmp9.1, %tmp8.1		; <i32> [#uses=2]
24	store i32 %tmp10.1, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 2)
25	%tmp8.2 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 2)		; <i32> [#uses=1]
26	%tmp9.2 = add i32 %tmp10.1, 1		; <i32> [#uses=1]
27	%tmp10.2 = add i32 %tmp9.2, %tmp8.2		; <i32> [#uses=2]
28	store i32 %tmp10.2, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 3)
29	%tmp8.3 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 3)		; <i32> [#uses=1]
30	%tmp9.3 = add i32 %tmp10.2, 1		; <i32> [#uses=1]
31	%tmp10.3 = add i32 %tmp9.3, %tmp8.3		; <i32> [#uses=2]
32	store i32 %tmp10.3, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 4)
33	%tmp8.4 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 4)		; <i32> [#uses=1]
34	%tmp9.4 = add i32 %tmp10.3, 1		; <i32> [#uses=1]
35	%tmp10.4 = add i32 %tmp9.4, %tmp8.4		; <i32> [#uses=2]
36	store i32 %tmp10.4, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 5)
37	%tmp8.5 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 5)		; <i32> [#uses=1]
38	%tmp9.5 = add i32 %tmp10.4, 1		; <i32> [#uses=1]
39	%tmp10.5 = add i32 %tmp9.5, %tmp8.5		; <i32> [#uses=2]
40	store i32 %tmp10.5, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 6)
41	%tmp8.6 = load i32* getelementptr ([1000 x i32]* @g1, i32 0, i32 6)		; <i32> [#uses=1]
42	%tmp9.6 = add i32 %tmp10.5, 1		; <i32> [#uses=1]
43	%tmp10.6 = add i32 %tmp9.6, %tmp8.6		; <i32> [#uses=1]
44	store i32 %tmp10.6, i32* getelementptr ([1000 x i32]* @g0, i32 0, i32 7)
45	ret void
46}
47
48