From a539f13021802253c792e94aec399caa06596b06 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lu=C3=ADs=20Ferreira?= <contact@lsferreira.net>
Date: Sun, 22 Jan 2023 12:50:42 +0000
Subject: [PATCH] driver: add support for a more generic diagnostic handler
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Luís Ferreira <contact@lsferreira.net>
---
 driver/codegenerator.cpp             | 68 ++++++++++++++++++++++++----
 tests/codegen/attr_warn_stack_size.d | 14 ++++++
 2 files changed, 73 insertions(+), 9 deletions(-)
 create mode 100644 tests/codegen/attr_warn_stack_size.d

diff --git a/driver/codegenerator.cpp b/driver/codegenerator.cpp
index e92c71866f5..d028e66c8c6 100644
--- a/driver/codegenerator.cpp
+++ b/driver/codegenerator.cpp
@@ -33,6 +33,7 @@
 #else
 #include "llvm/IR/RemarkStreamer.h"
 #endif
+#include "llvm/Demangle/Demangle.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/ToolOutputFile.h"
@@ -166,19 +167,68 @@ void inlineAsmDiagnosticHandler(const llvm::SMDiagnostic &d, void *context,
   inlineAsmDiagnostic(static_cast<IRState *>(context), d, locCookie);
 }
 #else
-struct InlineAsmDiagnosticHandler : public llvm::DiagnosticHandler {
+struct LDCDiagnosticHandler : public llvm::DiagnosticHandler {
   IRState *irs;
-  InlineAsmDiagnosticHandler(IRState *irs) : irs(irs) {}
+  LDCDiagnosticHandler(IRState *irs) : irs(irs) {}
 
     // return false to defer to LLVMContext::diagnose()
   bool handleDiagnostics(const llvm::DiagnosticInfo &DI) override {
-    if (DI.getKind() != llvm::DK_SrcMgr)
+    switch (DI.getKind())
+    {
+      case llvm::DK_SrcMgr:
+      {
+        const auto &DISM = llvm::cast<llvm::DiagnosticInfoSrcMgr>(DI);
+        switch (DISM.getSeverity())
+        {
+          case llvm::DS_Error:
+            ++global.errors;
+            break;
+          case llvm::DS_Warning:
+            ++global.warnings;
+            break;
+          case llvm::DS_Remark:
+          case llvm::DS_Note:
+            return false;
+        }
+
+        inlineAsmDiagnostic(irs, DISM.getSMDiag(), DISM.getLocCookie());
+        return true;
+      }
+      case llvm::DK_StackSize:
+      {
+        const auto &DISS = llvm::cast<llvm::DiagnosticInfoStackSize>(DI);
+#if LDC_LLVM_VER > 1400
+        llvm::StringRef fname;
+        unsigned line, column;
+        DISS.getLocation(fname, line, column);
+        const auto loc = Loc(fname.str().c_str(), line, column);
+#else
+        const auto loc = Loc(nullptr, 0, 0);
+#endif
+        switch (DISS.getSeverity())
+        {
+          case llvm::DS_Error:
+            error(loc, "stack frame size (%ld) exceeds limit (%ld) in '%s'",
+              DISS.getStackSize(),
+              DISS.getStackLimit(),
+              llvm::demangle(DISS.getFunction().getName().str()).c_str()
+            );
+            return true;
+          case llvm::DS_Warning:
+            warning(loc, "stack frame size (%ld) exceeds limit (%ld) in '%s'",
+              DISS.getStackSize(),
+              DISS.getStackLimit(),
+              llvm::demangle(DISS.getFunction().getName().str()).c_str()
+            );
+            return true;
+          case llvm::DS_Remark:
+          case llvm::DS_Note:
+            return false;
+        }
         return false;
-
-    const auto &DISM = llvm::cast<llvm::DiagnosticInfoSrcMgr>(DI);
-    if (DISM.getKind() == llvm::SourceMgr::DK_Error)
-      ++global.errors;
-    return inlineAsmDiagnostic(irs, DISM.getSMDiag(), DISM.getLocCookie());
+      }
+    }
+    return false;
   }
 };
 #endif
@@ -280,7 +330,7 @@ void CodeGenerator::writeAndFreeLLModule(const char *filename) {
   context_.setInlineAsmDiagnosticHandler(inlineAsmDiagnosticHandler, ir_);
 #else
   context_.setDiagnosticHandler(
-          std::make_unique<InlineAsmDiagnosticHandler>(ir_));
+          std::make_unique<LDCDiagnosticHandler>(ir_));
 #endif
 
   std::unique_ptr<llvm::ToolOutputFile> diagnosticsOutputFile =
diff --git a/tests/codegen/attr_warn_stack_size.d b/tests/codegen/attr_warn_stack_size.d
new file mode 100644
index 00000000000..ad872a51c35
--- /dev/null
+++ b/tests/codegen/attr_warn_stack_size.d
@@ -0,0 +1,14 @@
+module attr_warn_stack_size;
+// Test diagnostics for warnings on stack size
+
+// RUN: %ldc -wi -c %s 2>&1 | FileCheck %s
+
+import ldc.attributes;
+
+// CHECK: {{.*}}Warning: stack frame size (8) exceeds limit (1) in '_D20attr_warn_stack_size6foobarFiZf'
+@llvmAttr("warn-stack-size", "1")
+float foobar(int f)
+{
+    float _ = f;
+    return _;
+}