[KMSAN] Enable on PowerPC64 (#73611)

Enable -fsanitize=kernel-memory support in Clang.

Add tests.

---------

Co-authored-by: Nicholas Miehlbradt <nicholas@linux.ibm.com>

3 files changed, 155 insertions, 4 deletions

diff --git a/clang/lib/Driver/ToolChains/Linux.cpp b/clang/lib/Driver/ToolChains/Linux.cpp
index 2c583ac..2222dea 100644
--- a/clang/lib/Driver/ToolChains/Linux.cpp
+++ b/clang/lib/Driver/ToolChains/Linux.cpp
@@ -815,7 +815,7 @@ SanitizerMask Linux::getSupportedSanitizers() const {
   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsPowerPC64 || IsSystemZ ||
       IsLoongArch64 || IsRISCV64)
     Res |= SanitizerKind::Thread;
-  if (IsX86_64 || IsSystemZ)
+  if (IsX86_64 || IsSystemZ || IsPowerPC64)
     Res |= SanitizerKind::KernelMemory;
   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsX86 || IsMIPS || IsArmArch ||
       IsPowerPC64 || IsHexagon || IsLoongArch64 || IsRISCV64)
diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index ffb4e5b9..499f799 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -124,8 +124,9 @@
 ///      __msan_metadata_ptr_for_store_n(ptr, size);
 ///    Note that the sanitizer code has to deal with how shadow/origin pairs
 ///    returned by the these functions are represented in different ABIs. In
-///    the X86_64 ABI they are returned in RDX:RAX, and in the SystemZ ABI they
-///    are written to memory pointed to by a hidden parameter.
+///    the X86_64 ABI they are returned in RDX:RAX, in PowerPC64 they are
+///    returned in r3 and r4, and in the SystemZ ABI they are written to memory
+///    pointed to by a hidden parameter.
 ///  - TLS variables are stored in a single per-task struct. A call to a
 ///    function __msan_get_context_state() returning a pointer to that struct
 ///    is inserted into every instrumented function before the entry block;
@@ -139,7 +140,8 @@
 /// Also, KMSAN currently ignores uninitialized memory passed into inline asm
 /// calls, making sure we're on the safe side wrt. possible false positives.
 ///
-///  KernelMemorySanitizer only supports X86_64 and SystemZ at the moment.
+///  KernelMemorySanitizer only supports X86_64, SystemZ and PowerPC64 at the
+///  moment.
 ///
 //
 // FIXME: This sanitizer does not yet handle scalable vectors
diff --git a/llvm/test/Instrumentation/MemorySanitizer/PowerPC/kernel-ppc64le.ll b/llvm/test/Instrumentation/MemorySanitizer/PowerPC/kernel-ppc64le.ll
new file mode 100644
index 0000000..b4e472a
--- /dev/null
+++ b/llvm/test/Instrumentation/MemorySanitizer/PowerPC/kernel-ppc64le.ll
@@ -0,0 +1,149 @@
+; RUN: opt < %s -S -msan-kernel=1 -passes=msan 2>&1 | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-n32:64"
+target triple = "powerpc64le--linux"
+
+define void @Store1(ptr %p, i8 %x) sanitize_memory {
+entry:
+  store i8 %x, ptr %p
+  ret void
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Store1(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_store_1(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: store i8 {{.+}}, ptr [[SHADOW]]
+; CHECK: ret void
+
+define void @Store2(ptr %p, i16 %x) sanitize_memory {
+entry:
+  store i16 %x, ptr %p
+  ret void
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Store2(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_store_2(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: store i16 {{.+}}, ptr [[SHADOW]]
+; CHECK: ret void
+
+define void @Store4(ptr %p, i32 %x) sanitize_memory {
+entry:
+  store i32 %x, ptr %p
+  ret void
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Store4(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_store_4(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: store i32 {{.+}}, ptr [[SHADOW]]
+; CHECK: ret void
+
+define void @Store8(ptr %p, i64 %x) sanitize_memory {
+entry:
+  store i64 %x, ptr %p
+  ret void
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Store8(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_store_8(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: store i64 {{.+}}, ptr [[SHADOW]]
+; CHECK: ret void
+
+define void @Store16(ptr %p, i128 %x) sanitize_memory {
+entry:
+  store i128 %x, ptr %p
+  ret void
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Store16(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_store_n(ptr %p, i64 16)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: store i128 {{.+}}, ptr [[SHADOW]]
+; CHECK: ret void
+
+define i8 @Load1(ptr %p) sanitize_memory {
+entry:
+  %0 = load i8, ptr %p
+  ret i8 %0
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Load1(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_load_1(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: [[SHADOW_VAL:%[a-z0-9_]+]] = load i8, ptr [[SHADOW]]
+; CHECK: [[ORIGIN_VAL:%[a-z0-9_]+]] = load i32, ptr [[ORIGIN]]
+; CHECK: store i8 [[SHADOW_VAL]], ptr %retval_shadow
+; CHECK: store i32 [[ORIGIN_VAL]], ptr %retval_origin
+; CHECK: ret i8 {{.+}}
+
+define i16 @Load2(ptr %p) sanitize_memory {
+entry:
+  %0 = load i16, ptr %p
+  ret i16 %0
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Load2(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_load_2(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: [[SHADOW_VAL:%[a-z0-9_]+]] = load i16, ptr [[SHADOW]]
+; CHECK: [[ORIGIN_VAL:%[a-z0-9_]+]] = load i32, ptr [[ORIGIN]]
+; CHECK: store i16 [[SHADOW_VAL]], ptr %retval_shadow
+; CHECK: store i32 [[ORIGIN_VAL]], ptr %retval_origin
+; CHECK: ret i16 {{.+}}
+
+define i32 @Load4(ptr %p) sanitize_memory {
+entry:
+  %0 = load i32, ptr %p
+  ret i32 %0
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Load4(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_load_4(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: [[SHADOW_VAL:%[a-z0-9_]+]] = load i32, ptr [[SHADOW]]
+; CHECK: [[ORIGIN_VAL:%[a-z0-9_]+]] = load i32, ptr [[ORIGIN]]
+; CHECK: store i32 [[SHADOW_VAL]], ptr %retval_shadow
+; CHECK: store i32 [[ORIGIN_VAL]], ptr %retval_origin
+; CHECK: ret i32 {{.+}}
+
+define i64 @Load8(ptr %p) sanitize_memory {
+entry:
+  %0 = load i64, ptr %p
+  ret i64 %0
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Load8(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_load_8(ptr %p)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: [[SHADOW_VAL:%[a-z0-9_]+]] = load i64, ptr [[SHADOW]]
+; CHECK: [[ORIGIN_VAL:%[a-z0-9_]+]] = load i32, ptr [[ORIGIN]]
+; CHECK: store i64 [[SHADOW_VAL]], ptr %retval_shadow
+; CHECK: store i32 [[ORIGIN_VAL]], ptr %retval_origin
+; CHECK: ret i64 {{.+}}
+
+define i128 @Load16(ptr %p) sanitize_memory {
+entry:
+  %0 = load i128, ptr %p
+  ret i128 %0
+}
+
+; CHECK-LABEL: define {{[^@]+}}@Load16(
+; CHECK: [[META:%[a-z0-9_]+]] = call { ptr, ptr } @__msan_metadata_ptr_for_load_n(ptr %p, i64 16)
+; CHECK: [[SHADOW:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 0
+; CHECK: [[ORIGIN:%[a-z0-9_]+]] = extractvalue { ptr, ptr } [[META]], 1
+; CHECK: [[SHADOW_VAL:%[a-z0-9_]+]] = load i128, ptr [[SHADOW]]
+; CHECK: [[ORIGIN_VAL:%[a-z0-9_]+]] = load i32, ptr [[ORIGIN]]
+; CHECK: store i128 [[SHADOW_VAL]], ptr %retval_shadow
+; CHECK: store i32 [[ORIGIN_VAL]], ptr %retval_origin
+; CHECK: ret i128 {{.+}}