diff --git a/base/compiler/validation.jl b/base/compiler/validation.jl
index 1d12dc8e3d333..1b5ba3abf1ccf 100644
--- a/base/compiler/validation.jl
+++ b/base/compiler/validation.jl
@@ -24,7 +24,7 @@ const VALID_EXPR_HEADS = IdDict{Any,Any}(
     :foreigncall => 3:typemax(Int),
     :cfunction => 5:5,
     :isdefined => 1:1,
-    :simdloop => 0:0,
+    :simdloop => 1:1,
     :gc_preserve_begin => 0:typemax(Int),
     :gc_preserve_end => 0:typemax(Int),
     :thunk => 1:1,
diff --git a/base/simdloop.jl b/base/simdloop.jl
index 7493fbbd585a5..c5cccfddcbc7c 100644
--- a/base/simdloop.jl
+++ b/base/simdloop.jl
@@ -50,7 +50,7 @@ simd_outer_range(r) = 0:0
 @inline simd_index(r,j::Int,i) = (@inbounds ret = r[i+firstindex(r)]; ret)
 
 # Compile Expr x in context of @simd.
-function compile(x)
+function compile(x, ivdep)
     (isa(x, Expr) && x.head == :for) || throw(SimdError("for loop expected"))
     length(x.args) == 2 || throw(SimdError("1D for loop expected"))
     check_body!(x)
@@ -72,7 +72,7 @@ function compile(x)
                                 local $var = Base.simd_index($r,$j,$i)
                                 $(x.args[2])        # Body of loop
                                 $i += 1
-                                $(Expr(:simdloop))  # Mark loop as SIMD loop
+                                $(Expr(:simdloop, ivdep))  # Mark loop as SIMD loop
                             end
                         end
                         # Set index to last value just like a regular for loop would
@@ -86,7 +86,15 @@ function compile(x)
 end
 
 macro simd(forloop)
-    esc(compile(forloop))
+    esc(compile(forloop, false))
+end
+
+macro simd(ivdep, forloop)
+    if ivdep == :ivdep
+        esc(compile(forloop, true))
+    else
+        throw(SimdError("Only ivdep is valid as the first argument to @simd"))
+    end
 end
 
 end # module SimdLoop
diff --git a/src/codegen.cpp b/src/codegen.cpp
index 05978c785ea98..d15ef31fe0326 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -302,6 +302,7 @@ static Function *jl_alloc_obj_func;
 static Function *jl_newbits_func;
 static Function *jl_typeof_func;
 static Function *jl_simdloop_marker_func;
+static Function *jl_simdivdep_marker_func;
 static Function *jl_write_barrier_func;
 static Function *jlisa_func;
 static Function *jlsubtype_func;
@@ -4067,7 +4068,13 @@ static jl_cgval_t emit_expr(jl_codectx_t &ctx, jl_value_t *expr, ssize_t ssaval)
                     maybe_decay_untracked(boxed(ctx, ast))), true, jl_expr_type);
     }
     else if (head == simdloop_sym) {
-        ctx.builder.CreateCall(prepare_call(jl_simdloop_marker_func));
+        jl_value_t *ivdep = args[0];
+        assert(jl_expr_nargs(ex) == 1 && jl_is_bool(ivdep));
+        if (ivdep == jl_false) {
+            ctx.builder.CreateCall(prepare_call(jl_simdloop_marker_func));
+        } else {
+            ctx.builder.CreateCall(prepare_call(jl_simdivdep_marker_func));
+        }
         return jl_cgval_t();
     }
     else if (head == goto_ifnot_sym) {
@@ -7276,6 +7283,13 @@ static void init_julia_llvm_env(Module *m)
     jl_simdloop_marker_func->addFnAttr(Attribute::NoRecurse);
     jl_simdloop_marker_func->addFnAttr(Attribute::InaccessibleMemOnly);
 
+    jl_simdivdep_marker_func = Function::Create(FunctionType::get(T_void, {}, false),
+                                               Function::ExternalLinkage,
+                                               "julia.simdivdep_marker");
+    jl_simdivdep_marker_func->addFnAttr(Attribute::NoUnwind);
+    jl_simdivdep_marker_func->addFnAttr(Attribute::NoRecurse);
+    jl_simdivdep_marker_func->addFnAttr(Attribute::InaccessibleMemOnly);
+
     jl_typeof_func = Function::Create(FunctionType::get(T_prjlvalue, {T_prjlvalue}, false),
                                       Function::ExternalLinkage,
                                       "julia.typeof");
diff --git a/src/llvm-simdloop.cpp b/src/llvm-simdloop.cpp
index 8061495bbadb7..de40b0c9901ff 100644
--- a/src/llvm-simdloop.cpp
+++ b/src/llvm-simdloop.cpp
@@ -76,6 +76,8 @@ struct LowerSIMDLoop : public ModulePass {
     private:
     bool runOnModule(Module &M) override;
 
+    bool markSIMDLoop(Module &M, Function *marker, bool ivdep);
+
     /// Check if loop has "simd_loop" annotation.
     /// If present, the annotation is an MDNode attached to an instruction in the loop's latch.
     bool hasSIMDLoopMetadata( Loop *L) const;
@@ -173,13 +175,23 @@ void LowerSIMDLoop::enableUnsafeAlgebraIfReduction(PHINode *Phi, Loop *L) const
 bool LowerSIMDLoop::runOnModule(Module &M)
 {
     Function *simdloop_marker = M.getFunction("julia.simdloop_marker");
+    Function *simdivdep_marker = M.getFunction("julia.simdivdep_marker");
+
+    bool Changed = false;
+    if (simdloop_marker)
+        Changed |= markSIMDLoop(M, simdloop_marker, false);
+
+    if (simdivdep_marker)
+        Changed |= markSIMDLoop(M, simdivdep_marker, true);
 
-    if (!simdloop_marker)
-        return false;
+    return Changed;
+}
 
+bool LowerSIMDLoop::markSIMDLoop(Module &M, Function *marker, bool ivdep)
+{
     bool Changed = false;
     std::vector<Instruction*> ToDelete;
-    for (User *U : simdloop_marker->users()) {
+    for (User *U : marker->users()) {
         Instruction *I = cast<Instruction>(U);
         ToDelete.push_back(I);
         LoopInfo &LI = getAnalysis<LoopInfoWrapperPass>(*I->getParent()->getParent()).getLoopInfo();
@@ -189,6 +201,7 @@ bool LowerSIMDLoop::runOnModule(Module &M)
             continue;
 
         DEBUG(dbgs() << "LSL: simd_loop found\n");
+        DEBUG(dbgs() << "LSL: ivdep is: " << ivdep << "\n");
         BasicBlock *Lh = L->getHeader();
         DEBUG(dbgs() << "LSL: loop header: " << *Lh << "\n");
         MDNode *n = L->getLoopID();
@@ -203,15 +216,19 @@ bool LowerSIMDLoop::runOnModule(Module &M)
 
         MDNode *m = MDNode::get(Lh->getContext(), ArrayRef<Metadata *>(n));
 
-        // Mark memory references so that Loop::isAnnotatedParallel will return true for this loop.
-        for (BasicBlock *BB : L->blocks()) {
-            for (Instruction &I : *BB) {
-                if (I.mayReadOrWriteMemory()) {
-                    I.setMetadata(LLVMContext::MD_mem_parallel_loop_access, m);
-                }
+        // If ivdep is true we assume that there is no memory dependecy between loop iterations
+        // This is a fairly strong assumption and does often not hold true for generic code.
+        if (ivdep) {
+            // Mark memory references so that Loop::isAnnotatedParallel will return true for this loop.
+            for (BasicBlock *BB : L->blocks()) {
+               for (Instruction &I : *BB) {
+                   if (I.mayReadOrWriteMemory()) {
+                       I.setMetadata(LLVMContext::MD_mem_parallel_loop_access, m);
+                   }
+               }
             }
+            assert(L->isAnnotatedParallel());
         }
-        assert(L->isAnnotatedParallel());
 
         // Mark floating-point reductions as okay to reassociate/commute.
         for (BasicBlock::iterator I = Lh->begin(), E = Lh->end(); I != E; ++I) {
@@ -226,7 +243,7 @@ bool LowerSIMDLoop::runOnModule(Module &M)
 
     for (Instruction *I : ToDelete)
         I->deleteValue();
-    simdloop_marker->eraseFromParent();
+    marker->eraseFromParent();
 
     return Changed;
 }
diff --git a/test/bitarray.jl b/test/bitarray.jl
index 997ae0b1edc6a..ef5e1910f64aa 100644
--- a/test/bitarray.jl
+++ b/test/bitarray.jl
@@ -1575,3 +1575,13 @@ end
         end
     end
 end
+
+@testset "SIMD violations (issue #27482)" begin
+    @test all(any!(falses(10), trues(10, 10)))
+    @check_bit_operation any!(falses(10), trues(10, 10))
+    @check_bit_operation any!(falses(100), trues(100, 100))
+    @check_bit_operation any!(falses(1000), trues(1000, 100))
+    @check_bit_operation all!(falses(10), trues(10, 10))
+    @check_bit_operation all!(falses(100), trues(100, 100))
+    @check_bit_operation all!(falses(1000), trues(1000, 100))
+end
diff --git a/test/llvmpasses/simdloop.ll b/test/llvmpasses/simdloop.ll
index 9c44570ff0425..c427f318fe99a 100644
--- a/test/llvmpasses/simdloop.ll
+++ b/test/llvmpasses/simdloop.ll
@@ -1,5 +1,6 @@
 ; RUN: opt -load libjulia%shlibext -LowerSIMDLoop -S %s | FileCheck %s
 
+declare void @julia.simdivdep_marker()
 declare void @julia.simdloop_marker()
 
 define void @simd_test(double *%a, double *%b) {
@@ -15,7 +16,7 @@ loop:
   %cval = fadd double %aval, %bval
   store double %cval, double *%bptr
   %nexti = add i64 %i, 1
-  call void @julia.simdloop_marker()
+  call void @julia.simdivdep_marker()
   %done = icmp sgt i64 %nexti, 500
   br i1 %done, label %loopdone, label %loop
 loopdone:
@@ -32,6 +33,24 @@ loop:
 ; CHECK: llvm.mem.parallel_loop_access
   %aval = load double, double *%aptr
   %nextv = fsub double %v, %aval
+; CHECK: fsub fast double %v, %aval
+  %nexti = add i64 %i, 1
+  call void @julia.simdivdep_marker()
+  %done = icmp sgt i64 %nexti, 500
+  br i1 %done, label %loopdone, label %loop
+loopdone:
+  ret double %nextv
+}
+
+define double @simd_test_sub2(double *%a) {
+top:
+  br label %loop
+loop:
+  %i = phi i64 [0, %top], [%nexti, %loop]
+  %v = phi double [0.000000e+00, %top], [%nextv, %loop]
+  %aptr = getelementptr double, double *%a, i64 %i
+  %aval = load double, double *%aptr
+  %nextv = fsub double %v, %aval
 ; CHECK: fsub fast double %v, %aval
   %nexti = add i64 %i, 1
   call void @julia.simdloop_marker()
diff --git a/test/simdloop.jl b/test/simdloop.jl
index eae5e4e14f6af..97755be1c01a2 100644
--- a/test/simdloop.jl
+++ b/test/simdloop.jl
@@ -12,6 +12,13 @@ function simd_loop_example_from_manual(x, y, z)
     s
 end
 
+function simd_loop_axpy!(a, X, Y)
+    @simd ivdep for i in eachindex(X)
+        @inbounds Y[i] += a*X[i]
+    end
+    return Y
+end
+
 function simd_loop_with_multiple_reductions(x, y, z)
     # Use non-zero initial value to make sure reduction values include it.
     (s,t) = (one(eltype(x)),one(eltype(y)))
@@ -42,6 +49,11 @@ for T in [Int32,Int64,Float32,Float64]
         (s,t) = simd_loop_with_multiple_reductions(a,b,c)
         @test s==sum(a)+sum(c)+1
         @test t==2*sum(b)+1
+
+        X = ones(T, n)
+        Y = zeros(T, n)
+        simd_loop_axpy!(T(2), X, Y)
+        @test all(y->y==T(2), Y)
     end
 end