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| author | Kuba Brecka <kuba.brecka@gmail.com> | 2015-07-17 06:29:57 +0000 |
|---|---|---|
| committer | Kuba Brecka <kuba.brecka@gmail.com> | 2015-07-17 06:29:57 +0000 |
| commit | 37a5ffaca0ddf95a56da0deead8e01aa943a0aaf (patch) | |
| tree | e025b092bf3750d4cf8d4746b90ee4530978ea05 /llvm/test | |
| parent | 810329490aac73dccabab9aecdb50fade5e10a4f (diff) | |
| download | bcm5719-llvm-37a5ffaca0ddf95a56da0deead8e01aa943a0aaf.tar.gz bcm5719-llvm-37a5ffaca0ddf95a56da0deead8e01aa943a0aaf.zip | |
[asan] Fix invalid debug info for promotable allocas
Since r230724 ("Skip promotable allocas to improve performance at -O0"), there is a regression in the generated debug info for those non-instrumented variables. When inspecting such a variable's value in LLDB, you often get garbage instead of the actual value. ASan instrumentation is inserted before the creation of the non-instrumented alloca. The only allocas that are considered standard stack variables are the ones declared in the first basic-block, but the initial instrumentation setup in the function breaks that invariant.
This patch makes sure uninstrumented allocas stay in the first BB.
Differential Revision: http://reviews.llvm.org/D11179
llvm-svn: 242510
Diffstat (limited to 'llvm/test')
| -rw-r--r-- | llvm/test/Instrumentation/AddressSanitizer/debug_info_noninstrumented_alloca.ll | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/llvm/test/Instrumentation/AddressSanitizer/debug_info_noninstrumented_alloca.ll b/llvm/test/Instrumentation/AddressSanitizer/debug_info_noninstrumented_alloca.ll new file mode 100644 index 00000000000..7c38729ff43 --- /dev/null +++ b/llvm/test/Instrumentation/AddressSanitizer/debug_info_noninstrumented_alloca.ll @@ -0,0 +1,26 @@ +; This test checks that non-instrumented allocas stay in the first basic block. +; Only first-basic-block allocas are considered stack slots, and moving them +; breaks debug info. + +; RUN: opt < %s -asan -asan-module -S | FileCheck %s + +target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-apple-macosx10.10.0" + +define i32 @foo() sanitize_address { +entry: + ; Regular alloca, will get instrumented (forced by the ptrtoint below). + %instrumented = alloca i32, align 4 + + ; Won't be instrumented because of asan-skip-promotable-allocas. + %non_instrumented = alloca i32, align 4 + store i32 0, i32* %non_instrumented, align 4 + %value = load i32, i32* %non_instrumented, align 4 + + %ptr = ptrtoint i32* %instrumented to i64 + ret i32 %value +} + +; CHECK: entry: +; CHECK: %non_instrumented = alloca i32, align 4 +; CHECK: load i32, i32* @__asan_option_detect_stack_use_after_return |
