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Use when loop counters are initialized outside the loop and side-effecting expressions (like printf with branching arguments) are embedded in the for-statement's increment clause
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Based on SOC occupation classification
Use when printf statements output strings without trailing newlines
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Use when loop variables iterate over character values (e.g., ASCII codes) to represent different operations or choices
Use when code uses a loop to search for an input value in an array and then uses the found index for further computation
Use when code reads a fixed number of characters into an array and only accesses individual elements
| name | avoid-side-effects-in-loop-headers |
| description | Use when loop counters are initialized outside the loop and side-effecting expressions (like printf with branching arguments) are embedded in the for-statement's increment clause |
A KLEE-coverage code transformation. Applying it rewrites C source so symbolic execution explores more of the program's behavior.
When loop counters are initialized outside the loop and side-effecting expressions (like printf with branching arguments) are embedded in the for-statement's increment clause
Move side-effecting computations into the loop body and declare loop variables locally with standard init/condition/increment, separating control flow from output side effects
KLEE tracks symbolic state more efficiently when branching expressions appear in straightforward statement positions rather than buried in for-loop increment clauses; this exposes branch points clearly to the symbolic executor and reduces path-merging complexity, improving constraint solving and coverage replay
Before:
#include<stdio.h>
int main(){
int H,W,h,w,i=1,j;
scanf("%d%d%d%d",&H,&W,&h,&w);
if(H%h||W%w){
for(puts("Yes");i<=H;++i,puts("")) for(j=0;j<W;++j,printf("%d ",(i%h||j%w)?1000:-1000*(h*w-1)-1));
}else puts("No");
return 0;
}
After:
#include<stdio.h>
int main(){int H,W,h,w;scanf("%d%d%d%d",&H,&W,&h,&w);if(H%h||W%w){puts("Yes");for(int i=1;i<=H;++i,puts("")) for(int j=1;j<=W;++j)printf("%d ",(i%h||j%w)?1000:-1000*(h*w-1)-1);}else puts("No");return 0;}
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