Chris Lattner a92ff91a96 implement enough of the memset inference algorithm to recognize and insert ... memsets. This is still missing one important validity check, but this is enough to compile stuff like this: void test0(std::vector<char> &X) { for (std::vector<char>::iterator I = X.begin(), E = X.end(); I != E; ++I) *I = 0; } void test1(std::vector<int> &X) { for (long i = 0, e = X.size(); i != e; ++i) X[i] = 0x01010101; } With: $ clang t.cpp -S -o - -O2 -emit-llvm | opt -loop-idiom | opt -O3 | llc to: __Z5test0RSt6vectorIcSaIcEE: ## @_Z5test0RSt6vectorIcSaIcEE ## BB#0: ## %entry subq $8, %rsp movq (%rdi), %rax movq 8(%rdi), %rsi cmpq %rsi, %rax je LBB0_2 ## BB#1: ## %bb.nph subq %rax, %rsi movq %rax, %rdi callq ___bzero LBB0_2: ## %for.end addq $8, %rsp ret ... __Z5test1RSt6vectorIiSaIiEE: ## @_Z5test1RSt6vectorIiSaIiEE ## BB#0: ## %entry subq $8, %rsp movq (%rdi), %rax movq 8(%rdi), %rdx subq %rax, %rdx cmpq $4, %rdx jb LBB1_2 ## BB#1: ## %for.body.preheader andq $-4, %rdx movl $1, %esi movq %rax, %rdi callq _memset LBB1_2: ## %for.end addq $8, %rsp ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122573 91177308-0d34-0410-b5e6-96231b3b80d8		2010-12-26 23:42:51 +00:00
..
Hello	Since the Hello pass is built as a loadable dynamic library, don't try to convert it to new-style registration yet.	2010-10-07 00:31:16 +00:00
InstCombine	don't lose TD info	2010-12-25 20:52:04 +00:00
Instrumentation	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
IPO	reapply r121100 with a tweak to constant fold ConstExprs with TargetData	2010-12-07 04:33:29 +00:00
Scalar	implement enough of the memset inference algorithm to recognize and insert	2010-12-26 23:42:51 +00:00
Utils	don't lose TD info	2010-12-25 20:52:04 +00:00
Makefile	Revert r100896 and around - this breaks the only mingw32 buildbot we have.	2010-04-15 19:51:42 +00:00