Chris Lattner c6c1106909 Instead of storing operands as std::vector<Use>, just maintain a pointer ... and num operands in the User class. this allows us to embed the operands directly in the subclasses if possible. For example, for binary operators we store the two operands in the derived class. The has several effects: 1. it improves locality because the operands and instruction are together 2. it makes accesses to operands faster (one less load) if you access them through the derived class pointer. For example this: Value *GetBinaryOperatorOp(BinaryOperator *I, int i) { return I->getOperand(i); } Was compiled to: _Z19GetBinaryOperatorOpPN4llvm14BinaryOperatorEi: movl 4(%esp), %edx movl 8(%esp), %eax sall $4, %eax movl 24(%edx), %ecx addl %ecx, %eax movl (%eax), %eax ret and is now compiled to: _Z19GetBinaryOperatorOpPN4llvm14BinaryOperatorEi: movl 8(%esp), %eax movl 4(%esp), %edx sall $4, %eax addl %edx, %eax movl 44(%eax), %eax ret Accesses through "Instruction*" are unmodified. 3. This reduces memory consumption (by about 3%) by eliminating 1 word of vector overhead and a malloc header on a seperate object. 4. This speeds up gccas about 10% (both debug and release builds) on large things (such as 176.gcc). For example, it takes a debug build from 172.9 -> 155.6s and a release gccas from 67.7 -> 61.8s llvm-svn: 19883		2005-01-29 00:29:39 +00:00
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llvm	Instead of storing operands as std::vector<Use>, just maintain a pointer	2005-01-29 00:29:39 +00:00