commit 2d6a5670465cb3f1d811695a9f23e372508240d2
author Richard Smith <richard-llvm@metafoo.co.uk> Sat Jan 14 04:30:29 2012 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Sat Jan 14 04:30:29 2012 +0000
tree 3f440e630f5fc50c2977e0e052ba4a6974734583
parent 8568ee743406ac4bb23c9768a0dffd627fdbc579

constexpr irgen: Add irgen support for APValue::Struct, APValue::Union,
APValue::Array and APValue::MemberPointer. All APValue values can now be emitted
as constants.

Add new CGCXXABI entry point for emitting an APValue MemberPointer. The other
entrypoints dealing with constant member pointers are no longer necessary and
will be removed in a later change.

Switch codegen from using EvaluateAsRValue/EvaluateAsLValue to
VarDecl::evaluateValue. This performs caching and deals with the nasty cases in
C++11 where a non-const object's initializer can refer indirectly to
previously-initialized fields within the same object.

Building the intermediate APValue object incurs a measurable performance hit on
pathological testcases with huge initializer lists, so we continue to build IR
directly from the Expr nodes for array and record types outside of C++11.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148178 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGBlocks.cpp

diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp
index 8fc4344..e6ecb6a 100644
--- a/lib/CodeGen/CGBlocks.cpp
+++ b/lib/CodeGen/CGBlocks.cpp
@@ -215,6 +215,7 @@
 /// acceptable because we make no promises about address stability of
 /// captured variables.
 static llvm::Constant *tryCaptureAsConstant(CodeGenModule &CGM,
+                                            CodeGenFunction *CGF,
                                             const VarDecl *var) {
   QualType type = var->getType();
 
@@ -235,7 +236,7 @@
   const Expr *init = var->getInit();
   if (!init) return 0;
 
-  return CGM.EmitConstantExpr(init, var->getType());
+  return CGM.EmitConstantInit(*var, CGF);
 }
 
 /// Get the low bit of a nonzero character count.  This is the
@@ -278,7 +279,8 @@
 
 /// Compute the layout of the given block.  Attempts to lay the block
 /// out with minimal space requirements.
-static void computeBlockInfo(CodeGenModule &CGM, CGBlockInfo &info) {
+static void computeBlockInfo(CodeGenModule &CGM, CodeGenFunction *CGF,
+                             CGBlockInfo &info) {
   ASTContext &C = CGM.getContext();
   const BlockDecl *block = info.getBlockDecl();
 
@@ -342,7 +344,7 @@
 
     // Otherwise, build a layout chunk with the size and alignment of
     // the declaration.
-    if (llvm::Constant *constant = tryCaptureAsConstant(CGM, variable)) {
+    if (llvm::Constant *constant = tryCaptureAsConstant(CGM, CGF, variable)) {
       info.Captures[variable] = CGBlockInfo::Capture::makeConstant(constant);
       continue;
     }
@@ -497,7 +499,7 @@
 
   // Compute information about the layout, etc., of this block,
   // pushing cleanups as necessary.
-  computeBlockInfo(CGF.CGM, blockInfo);
+  computeBlockInfo(CGF.CGM, &CGF, blockInfo);
 
   // Nothing else to do if it can be global.
   if (blockInfo.CanBeGlobal) return;
@@ -604,7 +606,7 @@
   // layout for it.
   if (!blockExpr->getBlockDecl()->hasCaptures()) {
     CGBlockInfo blockInfo(blockExpr->getBlockDecl(), CurFn->getName());
-    computeBlockInfo(CGM, blockInfo);
+    computeBlockInfo(CGM, this, blockInfo);
     blockInfo.BlockExpression = blockExpr;
     return EmitBlockLiteral(blockInfo);
   }
@@ -911,7 +913,7 @@
   blockInfo.BlockExpression = blockExpr;
 
   // Compute information about the layout, etc., of this block.
-  computeBlockInfo(*this, blockInfo);
+  computeBlockInfo(*this, 0, blockInfo);
 
   // Using that metadata, generate the actual block function.
   llvm::Constant *blockFn;