use Dominik's coding icon for C++

lectures/parallelism/slides.qmd

@@ -63,7 +63,7 @@ FIXME
 * OpenMP uses something called threads
   * Wait until next week for a definition
 
-```c
+```c++
 #pragma omp parallel for
     for (int i = 0; i < N; ++i)
         a[i] = 2 * i;
@@ -149,13 +149,13 @@ Starting with batter for $N$ pancakes and 1 pan, we can scale by using $P$ pans
 
 # Reductions FIXME title should be more generic
 ## What is happening here?
-```c
+```c++
     int a[] = {2, 4, 6};
     for (int i = 0; i < N; ++i)
         sum = sum + a[i];
 ```
 ## What is happening here?
-```c
+```c++
     int a[] = {2, 4, 6};
 #pragma omp parallel for
     for (int i = 0; i < N; ++i)
@@ -164,7 +164,7 @@ Starting with batter for $N$ pancakes and 1 pan, we can scale by using $P$ pans
 [comment]: # (Can something go wrong?)
 
 ## Solution
-```c
+```c++
     int a[] = {2, 4, 6};
 #pragma omp parallel for reduction(+:sum)
     for (int i = 0; i < N; ++i)
@@ -173,7 +173,7 @@ Starting with batter for $N$ pancakes and 1 pan, we can scale by using $P$ pans
 
 # Doing stuff wrong
 ## What is going wrong here?
-```c
+```c++
     temp = 0;
 #pragma omp parallel for
     for (int i = 0; i < N; ++i) {
@@ -182,7 +182,7 @@ Starting with batter for $N$ pancakes and 1 pan, we can scale by using $P$ pans
     }
 ```
 ## Solution
-```c
+```c++
     temp = 0;
 #pragma omp parallel for private(temp)
     for (int i = 0; i < N; ++i) {
@@ -212,8 +212,16 @@ FIXME: Citation correct?!
 
 ## Precondition for parallel execution
 
+<br>
+
 *"Two consecutive instructions or code segments can be executed in parallel if they are **independent**."* 
 
+<br>
+
+:::{.fragment .info .smaller}
+What does **dependence** mean?
+:::
+
 ## Code and data dependence {.leftalign}
 
 
@@ -222,7 +230,7 @@ FIXME: Citation correct?!
 :::
 
 :::{.fragment .fade-in-then-semi-out fragment-index=2}
-```c 
+```c++ 
 a = b;
 c = a + b; //  flow dependence
 ```
@@ -233,7 +241,7 @@ c = a + b; //  flow dependence
 :::
 
 :::{.fragment .fade-in-then-semi-out fragment-index=4}
-```c
+```c++
 for (int i = 1; i < n ; i++) {
   a[i] = (a[i-1] > a[i]) ? a[i] + 1 : 1;
 } 
@@ -245,7 +253,7 @@ for (int i = 1; i < n ; i++) {
 :::
 
 :::{.fragment .fade-in-then-semi-out fragment-index=6}
-```c
+```c++
 a = b;
 b = 42; // read after write: a has an old value
 ```
@@ -257,7 +265,7 @@ b = 42; // read after write: a has an old value
 For data dependence, use the Bernstein's conditions: *"the intersection between read-write set, write-read set and write-write set of instructions is null"*.
 
 :::{.fragment}
-```c 
+```c++
 c = a + b;  // S1
 d = a - b;  // S2
 ```
@@ -302,7 +310,7 @@ S1 and S2 can be executed in parallel!
 
 :::{.notes}
 How about these two? replace a in S2 with c
-```c 
+```c++ 
 c = a + b;  // S1
 d = c - b;  // S2
 ```