From 673a9742603a6dc34b7f739f1321059dc6090a88 Mon Sep 17 00:00:00 2001
From: Sebastian Graf <SebastianGraf@t-online.de>
Date: Tue, 29 Jan 2013 22:38:12 +0100
Subject: [PATCH] Un-unroll static array,

[David Nadlinger] Note that DtoStructLiteralValues was/is used
only once across the codebase.
---
 gen/structs.cpp | 65 ++++++++++++-------------------------------------
 gen/structs.h   |  4 +--
 gen/toir.cpp    |  4 +--
 3 files changed, 20 insertions(+), 53 deletions(-)

diff --git a/gen/structs.cpp b/gen/structs.cpp
index 78b37212..43a4e5bb 100644
--- a/gen/structs.cpp
+++ b/gen/structs.cpp
@@ -149,39 +149,23 @@ LLValue* DtoIndexStruct(LLValue* src, StructDeclaration* sd, VarDeclaration* vd)
 //////////////////////////////////////////////////////////////////////////////////////////
 
 // helper function that adds zero bytes to a vector of constants
-size_t add_zeros(std::vector<llvm::Value*>& values, size_t diff)
+extern size_t add_zeros(std::vector<LLConstant*>& values, size_t diff);
+
+// return a constant array of type arrTypeD initialized with a constant value, or that constant value
+LLConstant* FillSArrayDims(Type* arrTypeD, LLConstant* init)
 {
-    size_t n = values.size();
-    bool is64 = global.params.is64bit;
-    while (diff)
+    if (arrTypeD->ty == Tsarray)
     {
-        if (is64 && diff % 8 == 0)
-        {
-            values.push_back(LLConstant::getNullValue(llvm::Type::getInt64Ty(gIR->context())));
-            diff -= 8;
-        }
-        else if (diff % 4 == 0)
-        {
-            values.push_back(LLConstant::getNullValue(llvm::Type::getInt32Ty(gIR->context())));
-            diff -= 4;
-        }
-        else if (diff % 2 == 0)
-        {
-            values.push_back(LLConstant::getNullValue(llvm::Type::getInt16Ty(gIR->context())));
-            diff -= 2;
-        }
-        else
-        {
-            values.push_back(LLConstant::getNullValue(llvm::Type::getInt8Ty(gIR->context())));
-            diff -= 1;
-        }
+        init = FillSArrayDims(arrTypeD->nextOf(), init);
+        size_t dim = static_cast<TypeSArray*>(arrTypeD)->dim->toUInteger();
+        LLArrayType* arrty = LLArrayType::get(init->getType(), dim);
+        return LLConstantArray::get(arrty, std::vector<LLConstant*>(dim, init));
     }
-    return values.size() - n;
+    return init;
 }
 
-std::vector<llvm::Value*> DtoStructLiteralValues(const StructDeclaration* sd,
-                                                 const std::vector<llvm::Value*>& inits,
-                                                 bool isConst)
+std::vector<LLConstant*> DtoStructLiteralValues(const StructDeclaration* sd,
+                                                const std::vector<LLConstant*>& inits)
 {
     // get arrays
     size_t nvars = sd->fields.dim;
@@ -200,7 +184,7 @@ std::vector<llvm::Value*> DtoStructLiteralValues(const StructDeclaration* sd,
     }
 
     // vector of values to build aggregate from
-    std::vector<llvm::Value*> values;
+    std::vector<LLConstant*> values;
 
     // offset trackers
     size_t lastoffset = 0;
@@ -264,24 +248,8 @@ std::vector<llvm::Value*> DtoStructLiteralValues(const StructDeclaration* sd,
 
         assert(nextVar == var);
 
-        // add any 0 padding needed before this field
-        if (!isConst && os > lastoffset + lastsize)
-        {
-            //printf("added %lu zeros\n", os - lastoffset - lastsize);
-            add_zeros(values, os - lastoffset - lastsize);
-        }
-
-        size_t repCount = 1;
-        // compute repCount to fill each array dimension
-        for (Type *varType = var->type;
-             varType->ty == Tsarray;
-             varType = varType->nextOf())
-        {
-            repCount *= static_cast<TypeSArray*>(varType)->dim->toUInteger();
-        }
-
-        // add the expression values
-        std::fill_n(std::back_inserter(values), repCount, inits[i]);
+        LLConstant* init = FillSArrayDims(var->type, inits[i]);
+        values.push_back(init);
 
         // update offsets
         lastoffset = os;
@@ -289,8 +257,7 @@ std::vector<llvm::Value*> DtoStructLiteralValues(const StructDeclaration* sd,
         // sometimes size of the initializer is less than size of the variable,
         // so make sure that lastsize is correct
         if (inits[i]->getType()->isSized())
-            lastsize = ceil(gDataLayout->getTypeSizeInBits(inits[i]->getType()) / 8.0);
-        else
+            sz = ceil(gDataLayout->getTypeSizeInBits(init->getType()) / 8.0);
 #endif
         lastsize = sz;
 
diff --git a/gen/structs.h b/gen/structs.h
index 165a3d46..8613744a 100644
--- a/gen/structs.h
+++ b/gen/structs.h
@@ -40,8 +40,8 @@ void DtoResolveStruct(StructDeclaration* sd);
 llvm::Constant* DtoConstStructInitializer(StructInitializer* si);
 
 /// Build values for a struct literal.
-std::vector<llvm::Value*> DtoStructLiteralValues(const StructDeclaration* sd,
-    const std::vector<llvm::Value*>& inits, bool isConst = false);
+std::vector<llvm::Constant*> DtoStructLiteralValues(const StructDeclaration* sd,
+    const std::vector<llvm::Constant*>& inits);
 
 /// Returns a boolean=true if the two structs are equal.
 llvm::Value* DtoStructEquals(TOK op, DValue* lhs, DValue* rhs);
diff --git a/gen/toir.cpp b/gen/toir.cpp
index 6e5bd2d2..afa46cf8 100644
--- a/gen/toir.cpp
+++ b/gen/toir.cpp
@@ -3046,7 +3046,7 @@ LLConstant* StructLiteralExp::toConstElem(IRState* p)
     sd->codegen(Type::sir);
 
     // get inits
-    std::vector<LLValue*> inits(sd->fields.dim, NULL);
+    std::vector<LLConstant*> inits(sd->fields.dim, NULL);
 
     size_t nexprs = elements->dim;;
     Expression** exprs = (Expression**)elements->data;
@@ -3056,7 +3056,7 @@ LLConstant* StructLiteralExp::toConstElem(IRState* p)
             inits[i] = exprs[i]->toConstElem(p);
 
     // vector of values to build aggregate from
-    std::vector<LLValue*> values = DtoStructLiteralValues(sd, inits, true);
+    std::vector<LLConstant*> values = DtoStructLiteralValues(sd, inits);
 
     // we know those values are constants.. cast them
     std::vector<LLConstant*> constvals(values.size(), NULL);