llvm-project/llvm/test/ThinLTO/X86/writeonly.ll

49 lines
2.2 KiB
LLVM

; Checks that we optimize writeonly variables and corresponding stores using llvm-lto
; -stats requires asserts
; REQUIRES: asserts
; RUN: opt -module-summary %s -o %t1.bc
; RUN: opt -module-summary %p/Inputs/index-const-prop.ll -o %t2.bc
; RUN: llvm-lto -thinlto-action=thinlink -o %t3.index.bc %t1.bc %t2.bc
; Check that we optimize write-only variables
; RUN: llvm-lto -thinlto-action=import -exported-symbol=main %t1.bc -thinlto-index=%t3.index.bc -o %t1.imported.bc -stats 2>&1 | FileCheck %s --check-prefix=STATS
; RUN: llvm-dis %t1.imported.bc -o - | FileCheck %s --check-prefix=IMPORT
; RUN: llvm-lto -thinlto-action=optimize %t1.imported.bc -o - | llvm-dis - -o - | FileCheck %s --check-prefix=OPTIMIZE
; IMPORT: @gBar = internal local_unnamed_addr global i32 0, align 4, !dbg !0
; IMPORT-NEXT: @gFoo.llvm.0 = internal unnamed_addr global i32 0, align 4, !dbg !5
; IMPORT: !DICompileUnit({{.*}})
; STATS: 2 module-summary-index - Number of live global variables marked write only
; Check that we've optimized out variables and corresponding stores
; OPTIMIZE-NOT: gFoo
; OPTIMIZE-NOT: gBar
; OPTIMIZE: i32 @main
; OPTIMIZE-NEXT: %1 = tail call i32 @rand()
; OPTIMIZE-NEXT: %2 = tail call i32 @rand()
; OPTIMIZE-NEXT: ret i32 0
; Confirm that with -propagate-attrs=false we no longer do write-only importing
; RUN: llvm-lto -propagate-attrs=false -thinlto-action=import -exported-symbol=main %t1.bc -thinlto-index=%t3.index.bc -o %t1.imported.bc -stats 2>&1 | FileCheck %s --check-prefix=STATS-NOPROP
; RUN: llvm-dis %t1.imported.bc -o - | FileCheck %s --check-prefix=IMPORT-NOPROP
; STATS-NOPROP-NOT: Number of live global variables marked write only
; IMPORT-NOPROP: @gBar = available_externally
; IMPORT-NOPROP-NEXT: @gFoo.llvm.0 = available_externally
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-linux-gnu"
@gBar = external global i32
; Should not be counted in the stats of live write only variables since it is
; dead and will be dropped anyway.
@gDead = internal unnamed_addr global i32 1, align 4
define i32 @main() local_unnamed_addr {
tail call void @baz()
ret i32 0
}
declare void @baz() local_unnamed_addr