diff options
| author | Alexander Potapenko <glider@google.com> | 2018-07-20 16:28:49 +0000 |
|---|---|---|
| committer | Alexander Potapenko <glider@google.com> | 2018-07-20 16:28:49 +0000 |
| commit | 7d86834e82ca6d4bd80a18d40c405001243e2d5a (patch) | |
| tree | ce836ad2829034fe45f0407eb8531f46579f1b55 /test | |
| parent | 8ec2a959fa2bbc0be28643f05759e149677c7a91 (diff) | |
[MSan] run materializeChecks() before materializeStores()
When pointer checking is enabled, it's important that every pointer is
checked before its value is used.
For stores MSan used to generate code that calculates shadow/origin
addresses from a pointer before checking it.
For userspace this isn't a problem, because the shadow calculation code
is quite simple and compiler is able to move it after the check on -O2.
But for KMSAN getShadowOriginPtr() creates a runtime call, so we want the
check to be performed strictly before that call.
Swapping materializeChecks() and materializeStores() resolves the issue:
both functions insert code before the given IR location, so the new
insertion order guarantees that the code calculating shadow address is
between the address check and the memory access.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@337571 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/Instrumentation/MemorySanitizer/check_access_address.ll | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/test/Instrumentation/MemorySanitizer/check_access_address.ll b/test/Instrumentation/MemorySanitizer/check_access_address.ll index 38f29b71cdf..21bb4125606 100644 --- a/test/Instrumentation/MemorySanitizer/check_access_address.ll +++ b/test/Instrumentation/MemorySanitizer/check_access_address.ll @@ -38,11 +38,14 @@ entry: ; CHECK-LABEL: @Store ; CHECK: load {{.*}} @__msan_param_tls +; Shadow calculations must happen after the check. +; CHECK-NOT: xor ; CHECK: icmp ; CHECK: br i1 ; CHECK: <label> ; CHECK: call void @__msan_warning_noreturn ; CHECK: <label> +; CHECK: xor ; CHECK: store ; CHECK: store i32 %x ; CHECK: ret void |