Scalar: Remove remaining ilist iterator implicit conversions

Remove remaining `ilist_iterator` implicit conversions from
LLVMScalarOpts.

This change exposed some scary behaviour in
lib/Transforms/Scalar/SCCP.cpp around line 1770.  This patch changes a
call from `Function::begin()` to `&Function::front()`, since the return
was immediately being passed into another function that takes a
`Function*`.  `Function::front()` started to assert, since the function
was empty.  Note that `Function::end()` does not point at a legal
`Function*` -- it points at an `ilist_half_node` -- so the other
function was getting garbage before.  (I added the missing check for
`Function::isDeclaration()`.)

Otherwise, no functionality change intended.

llvm-svn: 250211

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp b/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp
index 39c7738..b4102fe 100644
--- a/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp
@@ -112,7 +112,7 @@ bool LoopInstSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
 
       // Simplify instructions in the current basic block.
       for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE;) {
-        Instruction *I = BI++;
+        Instruction *I = &*BI++;
 
         // The first time through the loop ToSimplify is empty and we try to
         // simplify all instructions. On later iterations ToSimplify is not