| ; This test makes sure that these instructions are properly eliminated. |
| ; |
| |
| ; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep load |
| |
| %X = constant int 42 |
| %X2 = constant int 47 |
| %Y = constant [2 x { int, float }] [ { int, float } { int 12, float 1.0 }, |
| { int, float } { int 37, float 1.2312 } ] |
| %Z = constant [2 x { int, float }] zeroinitializer |
| |
| int %test1() { |
| %B = load int* %X |
| ret int %B |
| } |
| |
| float %test2() { |
| %A = getelementptr [2 x { int, float}]* %Y, long 0, long 1, ubyte 1 |
| %B = load float* %A |
| ret float %B |
| } |
| |
| |
| int %test3() { |
| %A = getelementptr [2 x { int, float}]* %Y, long 0, long 0, ubyte 0 |
| %B = load int* %A |
| ret int %B |
| } |
| |
| int %test4() { |
| %A = getelementptr [2 x { int, float}]* %Z, long 0, long 1, ubyte 0 |
| %B = load int* %A |
| ret int %B |
| } |
| |
| ; load (select (Cond, &V1, &V2)) --> select(Cond, load &V1, load &V2) |
| int %test5(bool %C) { |
| %Y = select bool %C, int* %X, int* %X2 |
| %Z = load int* %Y |
| ret int %Z |
| } |
| |
| ; load (phi (&V1, &V2, &V3)) --> phi(load &V1, load &V2, load &V3) |
| int %test6(bool %C) { |
| entry: |
| br bool %C, label %cond_true.i, label %cond_continue.i |
| |
| cond_true.i: |
| br label %cond_continue.i |
| |
| cond_continue.i: |
| %mem_tmp.i.0 = phi int* [ %X, %cond_true.i ], [ %X2, %entry ] |
| %tmp.3 = load int* %mem_tmp.i.0 |
| ret int %tmp.3 |
| } |
| |
| int %test7(int %X) { |
| %V = getelementptr int* null, int %X |
| %R = load int* %V |
| ret int %R |
| } |
| |
| int %test8(int* %P) { |
| store int 1, int* %P |
| %X = load int* %P ;; Trivial store->load forwarding |
| ret int %X |
| } |
| |
| int %test9(int* %P) { |
| %X = load int* %P ;; Trivial load cse |
| %Y = load int* %P |
| %Z = sub int %X, %Y |
| ret int %Z |
| } |
| |
| int %test10(bool %C, int* %P, int* %Q) { |
| br bool %C, label %T, label %F |
| T: |
| store int 1, int* %Q |
| store int 0, int* %P |
| br label %C |
| F: |
| store int 0, int* %P |
| br label %C |
| C: |
| %V = load int* %P ;; always 0 |
| ret int %V |
| } |