The basic issue is that isel (very reasonably!) expects conditional branches
to be folded, so CGP leaving around a bunch dead computation feeding
conditional branches isn't such a good idea. Just fold branches on constants
into unconditional branches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123526
91177308-0d34-0410-b5e6-
96231b3b80d8
if (CallInst *CI = dyn_cast<CallInst>(I))
return OptimizeCallInst(CI);
+ if (isa<TerminatorInst>(I))
+ return ConstantFoldTerminator(I->getParent());
+
return false;
}
target triple = "x86_64-apple-darwin10.0.0"
; CHECK: @test1
+; objectsize should fold to a constant, which causes the branch to fold to an
+; uncond branch.
+; rdar://8785296
define i32 @test1(i8* %ptr) nounwind ssp noredzone align 2 {
entry:
%0 = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%1 = icmp ugt i64 %0, 3
br i1 %1, label %T, label %trap
-; CHECK: br i1 true, label
+; CHECK: br label %T
trap: ; preds = %0, %entry
tail call void @llvm.trap() noreturn nounwind
unreachable