[llvm] [AMDGPU] Introduce address sanitizer instrumentation for LDS lowered by amdgpu-sw-lower-lds pass (PR #89208)

[Matt Arsenault via llvm-commits]

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@@ -1239,6 +1236,290 @@ void AddressSanitizerPass::printPipeline(
   OS << '>';
 }
 
+static uint64_t getRedzoneSizeForScale(int MappingScale) {
+  // Redzone used for stack and globals is at least 32 bytes.
+  // For scales 6 and 7, the redzone has to be 64 and 128 bytes respectively.
+  return std::max(32U, 1U << MappingScale);
+}
+
+static uint64_t getMinRedzoneSizeForGlobal(int Scale) {
+  return getRedzoneSizeForScale(Scale);
+}
+
+static uint64_t getRedzoneSizeForGlobal(int Scale, uint64_t SizeInBytes) {
+  constexpr uint64_t kMaxRZ = 1 << 18;
+  const uint64_t MinRZ = getMinRedzoneSizeForGlobal(Scale);
+
+  uint64_t RZ = 0;
+  if (SizeInBytes <= MinRZ / 2) {
+    // Reduce redzone size for small size objects, e.g. int, char[1]. MinRZ is
+    // at least 32 bytes, optimize when SizeInBytes is less than or equal to
+    // half of MinRZ.
+    RZ = MinRZ - SizeInBytes;
+  } else {
+    // Calculate RZ, where MinRZ <= RZ <= MaxRZ, and RZ ~ 1/4 * SizeInBytes.
+    RZ = std::clamp((SizeInBytes / MinRZ / 4) * MinRZ, MinRZ, kMaxRZ);
+
+    // Round up to multiple of MinRZ.
+    if (SizeInBytes % MinRZ)
+      RZ += MinRZ - (SizeInBytes % MinRZ);
+  }
+
+  assert((RZ + SizeInBytes) % MinRZ == 0);
+
+  return RZ;
+}
+
+static GlobalVariable *getKernelSwLDSGlobal(Module &M, Function &F) {
+  SmallString<64> KernelLDSName("llvm.amdgcn.sw.lds.");
+  KernelLDSName += F.getName();
+  return M.getNamedGlobal(KernelLDSName);
+}
+
+static GlobalVariable *getKernelSwLDSMetadataGlobal(Module &M, Function &F) {
+  SmallString<64> KernelLDSName("llvm.amdgcn.sw.lds.");
+  KernelLDSName += F.getName();
+  KernelLDSName += ".md";
+  return M.getNamedGlobal(KernelLDSName);
+}
+
+static GlobalVariable *getKernelSwDynLDSGlobal(Module &M, Function &F) {
+  SmallString<64> KernelLDSName("llvm.amdgcn.");
+  KernelLDSName += F.getName();
+  KernelLDSName += ".dynlds";
+  return M.getNamedGlobal(KernelLDSName);
+}
+
+static GlobalVariable *getKernelSwLDSBaseGlobal(Module &M) {
+  SmallString<64> KernelLDSName("llvm.amdgcn.sw.lds.base.table");
+  return M.getNamedGlobal(KernelLDSName);
+}
+
+static void updateLDSSizeFnAttr(Function *Func, uint32_t Offset,
+                                bool UsesDynLDS) {
+  if (Offset != 0) {
+    std::string Buffer;
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arsenm wrote:

SmallString + raw_svector_ostream 

https://github.com/llvm/llvm-project/pull/89208