Rollup merge of #138731 - Zalathar:llvm-expansion, r=jieyouxu

coverage: Add LLVM plumbing for expansion regions

This is currently unused, but paves the way for future work on expansion regions without having to worry about the FFI parts.

The span conversion refactoring is only loosely related, but I've included it here because it would conflict with the main changes in `fill_region_tables`, and is pretty straightforward on its own.

1 files changed, 16 insertions, 0 deletions

diff --git a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
index 0471baa1f9c..b8884486c33 100644
--- a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
@@ -78,6 +78,13 @@ struct LLVMRustCoverageCodeRegion {
 };
 
 // Must match the layout of
+// `rustc_codegen_llvm::coverageinfo::ffi::ExpansionRegion`.
+struct LLVMRustCoverageExpansionRegion {
+  LLVMRustCoverageSpan Span;
+  uint32_t ExpandedFileID;
+};
+
+// Must match the layout of
 // `rustc_codegen_llvm::coverageinfo::ffi::BranchRegion`.
 struct LLVMRustCoverageBranchRegion {
   LLVMRustCoverageSpan Span;
@@ -151,6 +158,8 @@ extern "C" void LLVMRustCoverageWriteFunctionMappingsToBuffer(
     const unsigned *VirtualFileMappingIDs, size_t NumVirtualFileMappingIDs,
     const LLVMRustCounterExpression *RustExpressions, size_t NumExpressions,
     const LLVMRustCoverageCodeRegion *CodeRegions, size_t NumCodeRegions,
+    const LLVMRustCoverageExpansionRegion *ExpansionRegions,
+    size_t NumExpansionRegions,
     const LLVMRustCoverageBranchRegion *BranchRegions, size_t NumBranchRegions,
     const LLVMRustCoverageMCDCBranchRegion *MCDCBranchRegions,
     size_t NumMCDCBranchRegions,
@@ -179,6 +188,13 @@ extern "C" void LLVMRustCoverageWriteFunctionMappingsToBuffer(
         Region.Span.ColumnStart, Region.Span.LineEnd, Region.Span.ColumnEnd));
   }
 
+  // Expansion regions:
+  for (const auto &Region : ArrayRef(ExpansionRegions, NumExpansionRegions)) {
+    MappingRegions.push_back(coverage::CounterMappingRegion::makeExpansion(
+        Region.Span.FileID, Region.ExpandedFileID, Region.Span.LineStart,
+        Region.Span.ColumnStart, Region.Span.LineEnd, Region.Span.ColumnEnd));
+  }
+
   // Branch regions:
   for (const auto &Region : ArrayRef(BranchRegions, NumBranchRegions)) {
     MappingRegions.push_back(coverage::CounterMappingRegion::makeBranchRegion(