| ; Test the behavior of GlobalDCE in conjunction with comdats. |
| ; |
| ; RUN: opt < %s -passes=globaldce -S | FileCheck %s |
| |
| ; First test checks that if one function in a comdat group is used, both other |
| ; functions and other globals even if unused will be preserved. |
| $test1_c = comdat any |
| ; CHECK: $test1_c = comdat any |
| |
| ; Second test checks that if one function in a comdat group is used, both other |
| ; functions and other globals even if unused will be preserved. |
| $test2_c = comdat any |
| ; CHECK: $test2_c = comdat any |
| |
| ; Third test checks that calling a function in a comdat group with an alias |
| ; preserves the alias. |
| $test3_c = comdat any |
| ; CHECK: $test3_c = comdat any |
| |
| ; Fourth test checks that calling an alias in a comdat group with a function |
| ; preserves the function. (This is the trivial case as the alias uses the |
| ; function.) |
| $test4_c = comdat any |
| ; CHECK: $test4_c = comdat any |
| |
| ; Fifth test checks that calling a function in a comdat group that is used as |
| ; the resolver of an ifunc doesn't preserve that ifunc. ifunc symbols don't |
| ; participate in the comdat group of their resolver function as they are |
| ; considered separate objects. |
| $test5_c = comdat any |
| ; CHECK: $test5_c = comdat any |
| |
| ; Sixth test checks that calling an ifunc whose resolver is in a comdat group |
| ; preserves the resolver. This is the trivial case as the ifunc uses the |
| ; resolver. |
| $test6_c = comdat any |
| ; CHECK: $test6_c = comdat any |
| |
| ; Seventh test checks that we can eliminate a comdat when it has only one dead function participant. |
| $test7_c = comdat any |
| ; CHECK-NOT: $test7_c = comdat any |
| |
| ; Eighth test checks that we can eliminate a comdat when it has only one dead global participant. |
| $test8_c = comdat any |
| ; CHECK-NOT: $test8_c = comdat any |
| |
| ; Ninth test checks that we can eliminate a comdat when there are multiple |
| ; dead participants. |
| $test9_c = comdat any |
| ; CHECK-NOT: $test9_c = comdat any |
| |
| ; Tenth test checks that we can eliminate a comdat when it has multiple |
| ; participants that form internal cyclic uses but are never used externally and |
| ; thus the entire ifunc can safely be eliminated. |
| $test10_c = comdat any |
| ; CHECK-NOT: $test10_c = comdat any |
| |
| @test1_gv = linkonce_odr unnamed_addr global i32 42, comdat($test1_c) |
| ; CHECK: @test1_gv = linkonce_odr unnamed_addr global |
| |
| @test2_used = linkonce_odr unnamed_addr global i32 42, comdat($test2_c) |
| ; CHECK: @test2_used = linkonce_odr unnamed_addr global |
| |
| @test2_gv = linkonce_odr unnamed_addr global i32 42, comdat($test2_c) |
| ; CHECK: @test2_gv = linkonce_odr unnamed_addr global |
| |
| @test8_gv = linkonce_odr unnamed_addr global i32 42, comdat($test8_c) |
| ; CHECK-NOT: @test8_gv |
| |
| @test9_gv = linkonce_odr unnamed_addr global i32 42, comdat($test9_c) |
| ; CHECK-NOT: @test9_gv |
| |
| @test10_gv = linkonce_odr unnamed_addr global void ()* @test10_f, comdat($test10_c) |
| ; CHECK-NOT: @test10_gv |
| |
| @test3_a = linkonce_odr unnamed_addr alias void (), void ()* @test3_f |
| ; CHECK: @test3_a = linkonce_odr unnamed_addr alias |
| |
| @test4_a = linkonce_odr unnamed_addr alias void (), void ()* @test4_f |
| ; CHECK: @test4_a = linkonce_odr unnamed_addr alias |
| |
| @test10_a = linkonce_odr unnamed_addr alias void (), void ()* @test10_g |
| ; CHECK-NOT: @test10_a |
| |
| @test5_if = linkonce_odr ifunc void (), void ()* ()* @test5_f |
| ; CHECK-NOT: @test5_if |
| |
| @test6_if = linkonce_odr ifunc void (), void ()* ()* @test6_f |
| ; CHECK: @test6_if = linkonce_odr ifunc |
| |
| ; This function is directly used and so cannot be eliminated. |
| define linkonce_odr void @test1_used() comdat($test1_c) { |
| ; CHECK: define linkonce_odr void @test1_used() |
| entry: |
| ret void |
| } |
| |
| define linkonce_odr void @test1_f() comdat($test1_c) { |
| ; CHECK: define linkonce_odr void @test1_f() |
| entry: |
| ret void |
| } |
| |
| ; Now test that a function, global variable, alias, and ifunc in the same |
| ; comdat are kept. |
| define linkonce_odr void @test2_f() comdat($test2_c) { |
| ; CHECK: define linkonce_odr void @test2_f() |
| entry: |
| ret void |
| } |
| |
| define linkonce_odr void @test3_f() comdat($test3_c) { |
| ; CHECK: define linkonce_odr void @test3_f() |
| entry: |
| ret void |
| } |
| |
| define linkonce_odr void @test4_f() comdat($test4_c) { |
| ; CHECK: define linkonce_odr void @test4_f() |
| entry: |
| ret void |
| } |
| |
| declare void @test_external() |
| |
| define linkonce_odr void ()* @test5_f() comdat($test5_c) { |
| ; CHECK: define linkonce_odr void ()* @test5_f() |
| entry: |
| ret void ()* @test_external |
| } |
| |
| define linkonce_odr void ()* @test6_f() comdat($test6_c) { |
| ; CHECK: define linkonce_odr void ()* @test6_f() |
| entry: |
| ret void ()* @test_external |
| } |
| |
| define linkonce_odr void @test7_f() comdat($test7_c) { |
| ; CHECK-NOT: @test7_f |
| entry: |
| ret void |
| } |
| |
| define linkonce_odr void @test9_f() comdat($test9_c) { |
| ; CHECK-NOT: @test9_f |
| entry: |
| ret void |
| } |
| |
| define linkonce_odr void @test10_f() comdat($test10_c) { |
| ; CHECK-NOT: @test10_f |
| entry: |
| %gv = load void ()*, void ()** @test10_gv |
| call void @test10_a() |
| ret void |
| } |
| |
| define linkonce_odr void @test10_g() comdat($test10_c) { |
| ; CHECK-NOT: @test10_g |
| entry: |
| call void @test10_f() |
| ret void |
| } |
| |
| |
| ; An external function to pin as "used" various things above that shouldn't be |
| ; eliminated. |
| define void @external_user() { |
| call void @test1_used() |
| %gv = load i32, i32* @test2_used |
| |
| call void @test3_f() |
| call void @test4_a() |
| |
| %fptr = call void() *@test5_f() |
| call void @test6_if() |
| ret void |
| } |