ASan: wrap mapping scale and offset in a struct and make it a member of ASan passes. Add test for non-default mapping scale and offset. No functionality change

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172610 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 41 insertions, 0 deletions

diff --git a/test/Instrumentation/AddressSanitizer/different_scale_and_offset.ll b/test/Instrumentation/AddressSanitizer/different_scale_and_offset.ll
new file mode 100644
index 0000000000..c07069c2dc
--- /dev/null
+++ b/test/Instrumentation/AddressSanitizer/different_scale_and_offset.ll
@@ -0,0 +1,41 @@
+; Test non-default shadow mapping scale and offset.
+;
+; RUN: opt < %s -asan -asan-mapping-scale=2 -asan-mapping-offset-log=0 -S | FileCheck %s
+
+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"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Test that ASan tells scale and offset to runtime.
+; CHECK: @__asan_mapping_offset = linkonce_odr constant i64 0
+; CHECK: @__asan_mapping_scale = linkonce_odr constant i64 2
+
+define i32 @test_load(i32* %a) address_safety {
+; CHECK: @test_load
+; CHECK-NOT: load
+; CHECK:   %[[LOAD_ADDR:[^ ]*]] = ptrtoint i32* %a to i64
+; CHECK:   lshr i64 %[[LOAD_ADDR]], 2
+
+; No need in shift for zero offset.
+; CHECK-NOT:  or i64
+
+; CHECK:   %[[LOAD_SHADOW_PTR:[^ ]*]] = inttoptr
+; CHECK:   %[[LOAD_SHADOW:[^ ]*]] = load i8* %[[LOAD_SHADOW_PTR]]
+; CHECK:   icmp ne i8
+; CHECK:   br i1 %{{.*}}, label %{{.*}}, label %{{.*}}
+
+; No need in slow path for i32 and mapping scale equal to 2.
+; CHECK-NOT:   and i64 %[[LOAD_ADDR]]
+;
+; The crash block reports the error.
+; CHECK:   call void @__asan_report_load4(i64 %[[LOAD_ADDR]])
+; CHECK:   unreachable
+;
+; The actual load.
+; CHECK:   %tmp1 = load i32* %a
+; CHECK:   ret i32 %tmp1
+
+entry:
+  %tmp1 = load i32* %a
+  ret i32 %tmp1
+}
+