llvm-6502/test/Instrumentation/AddressSanitizer/stack_layout.ll
Anna Zaks f891336a25 [asan] Skip promotable allocas to improve performance at -O0
Currently, the ASan executables built with -O0 are unnecessarily slow.
The main reason is that ASan instrumentation pass inserts redundant
checks around promotable allocas. These allocas do not get instrumented
under -O1 because they get converted to virtual registered by mem2reg.
With this patch, ASan instrumentation pass will only instrument non
promotable allocas, giving us a speedup of 39% on a collection of
benchmarks with -O0. (There is no measurable speedup at -O1.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230724 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 03:12:36 +00:00

80 lines
2.5 KiB
LLVM

; Test the ASan's stack layout.
; More tests in tests/Transforms/Utils/ASanStackFrameLayoutTest.cpp
; RUN: opt < %s -asan -asan-module -asan-stack-dynamic-alloca=0 -S \
; RUN: | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-STATIC
; RUN: opt < %s -asan -asan-module -asan-stack-dynamic-alloca=1 -S \
; RUN: | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-DYNAMIC
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
declare void @Use(i8*)
; CHECK: private unnamed_addr constant{{.*}}3 32 10 3 XXX 64 20 3 YYY 128 30 3 ZZZ
; CHECK: private unnamed_addr constant{{.*}}3 32 5 3 AAA 64 55 3 BBB 160 555 3 CCC
; CHECK: private unnamed_addr constant{{.*}}3 256 128 3 CCC 448 128 3 BBB 608 128 3 AAA
define void @Func1() sanitize_address {
entry:
; CHECK-LABEL: Func1
; CHECK-STATIC: alloca [192 x i8]
; CHECK-DYNAMIC: alloca i8, i64 192
; CHECK-NOT: alloca
; CHECK: ret void
%XXX = alloca [10 x i8], align 1
%YYY = alloca [20 x i8], align 1
%ZZZ = alloca [30 x i8], align 1
%arr1.ptr = bitcast [10 x i8]* %XXX to i8*
store volatile i8 0, i8* %arr1.ptr
%arr2.ptr = bitcast [20 x i8]* %YYY to i8*
store volatile i8 0, i8* %arr2.ptr
%arr3.ptr = bitcast [30 x i8]* %ZZZ to i8*
store volatile i8 0, i8* %arr3.ptr
ret void
}
define void @Func2() sanitize_address {
entry:
; CHECK-LABEL: Func2
; CHECK-STATIC: alloca [864 x i8]
; CHECK-DYNAMIC: alloca i8, i64 864
; CHECK-NOT: alloca
; CHECK: ret void
%AAA = alloca [5 x i8], align 1
%BBB = alloca [55 x i8], align 1
%CCC = alloca [555 x i8], align 1
%arr1.ptr = bitcast [5 x i8]* %AAA to i8*
store volatile i8 0, i8* %arr1.ptr
%arr2.ptr = bitcast [55 x i8]* %BBB to i8*
store volatile i8 0, i8* %arr2.ptr
%arr3.ptr = bitcast [555 x i8]* %CCC to i8*
store volatile i8 0, i8* %arr3.ptr
ret void
}
; Check that we reorder vars according to alignment and handle large alignments.
define void @Func3() sanitize_address {
entry:
; CHECK-LABEL: Func3
; CHECK-STATIC: alloca [768 x i8]
; CHECK-DYNAMIC: alloca i8, i64 768
; CHECK-NOT: alloca
; CHECK: ret void
%AAA = alloca [128 x i8], align 16
%BBB = alloca [128 x i8], align 64
%CCC = alloca [128 x i8], align 256
%arr1.ptr = bitcast [128 x i8]* %AAA to i8*
store volatile i8 0, i8* %arr1.ptr
%arr2.ptr = bitcast [128 x i8]* %BBB to i8*
store volatile i8 0, i8* %arr2.ptr
%arr3.ptr = bitcast [128 x i8]* %CCC to i8*
store volatile i8 0, i8* %arr3.ptr
ret void
}