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Hi,

I am trying to do a transformation pass in "opt".

---Snip--

#pragma omp parallel for

for (int j=0; j<1000000; j++)

b\[j\] = a\[j\]\*scalar;

---Snip----

For the above loop under -fopenmp:

1\. How to check if the loop I am working is a parallel loop (i.e. discover the "openmp" hint)

I tired Loop->isAnnotatedParallel(), but it is returning false.

2\. Is there some way to discover the original bounds of the loop?

I could see the original bounds are passed at the start of the "@.omp\_outlined" function.

---Snip----

%0 = bitcast i32\* %.omp.lb to i8\*

call void @llvm.lifetime.start.p0i8(i64 4, i8\* nonnull %0) #4

store i32 0, i32\* %.omp.lb, align 4, !tbaa !7 <== lower bound

%1 = bitcast i32\* %.omp.ub to i8\*

call void @llvm.lifetime.start.p0i8(i64 4, i8\* nonnull %1) #4

store i32 999999, i32\* %.omp.ub, align 4, !tbaa !7 <== upper bound.

---Snip----

Now the loop is

---Snip----

omp.inner.for.body: ; preds = %omp.inner.for.body.preheader, %omp.inner.for.body

%indvars.iv = phi i64 \[ %8, %omp.inner.for.body.preheader \], \[ %indvars.iv.next, %omp.inner.for.body \]

.......

%cmp1 = icmp slt i64 %indvars.iv, %9

br i1 %cmp1, label %omp.inner.for.body, label %omp.loop.exit

---Snip----

%8 is lower bound

%9 is maximum of upper bound and 999999.

I could do a backward walk and figure out what the bounds are initially set to?

Are there a better ways for doing it example using SCEV ?

regards,

Venkat.