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view tools/binding/llvmsample1.d @ 1275:bedf0bfb8fdb
Implement first D-specific optimization pass: -simplify-drtcalls.
It uses the machinery of the standard -simplify-libcalls pass, but optimizes
calls to the D runtime instead of calls to C libraries.
At the moment, these optimizations are implemented by this pass:
- Avoid the runtime call for `arr.length = newlen` if it can determine that
the new length isn't longer than the old one.
- Ditto for `cast(T[]) arr` if it will clearly always succeed.
(e.g. if the length of the original array is zero, or if the old element
size is a multiple of the new element size)
author | Frits van Bommel <fvbommel wxs.nl> |
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date | Tue, 28 Apr 2009 21:58:06 +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"); }