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view tools/binding/llvmsample1.d @ 1499:df11cdec45a2
Another shot at fixing the issues with (constant) struct literals and their addresses. See DMD2682, #218, #324.
The idea is to separate the notion of const from 'this variable can always be
replaced with its initializer' in the frontend. To do that, I introduced
Declaration::isSameAsInitializer, which is overridden in VarDeclaration to
return false for constants that have a struct literal initializer.
So
{{{
const S s = S(5);
void foo() { auto ps = &s; }
// is no longer replaced by
void foo() { auto ps = &(S(5)); }
}}}
To make taking the address of a struct constant with a struct-initializer
outside of function scope possible, I made sure that AddrExp::optimize doesn't
try to run the argument's optimization with WANTinterpret - that'd again
replace the constant with a struct literal temporary.
author | Christian Kamm <kamm incasoftware de> |
---|---|
date | Sun, 14 Jun 2009 19:49:58 +0200 |
parents | 1ba61de8796b |
children |
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// simple hello world sample of D LLVM module llvmsample1; import llvm.llvm; void main() { // create module auto m = new Module("sample1"); scope(exit) m.dispose(); // declare string auto chello = ConstantArray.GetString("Hello World!\n", true); auto hello = m.addGlobal(chello.type, "hellostring"); hello.initializer = chello; hello.linkage = Linkage.Internal; hello.globalConstant = true; // declare printf auto printfType = FunctionType.Get(Type.Int32, [ PointerType.Get(Type.Int8) ], true); auto llprintf = m.addFunction(printfType, "printf"); // declare main auto mainType = FunctionType.Get(Type.Int32, null); auto llmain = m.addFunction(mainType, "main"); // create builder auto b = new Builder; scope(exit) b.dispose(); // create main body block auto bb = llmain.appendBasicBlock("entry"); b.positionAtEnd(bb); // call printf auto zero = ConstantInt.GetU(Type.Int32, 0); auto helloptr = b.buildGEP(hello, [ zero, zero ], "str"); helloptr.dump(); auto args = [ helloptr ]; auto call = b.buildCall(llprintf, args, ""); // return 0 b.buildRet(ConstantInt.GetS(Type.Int32, 0)); // write bitcode m.writeBitcodeToFile("sample1.bc"); }