// RUN: %clang -target mipsel-unknown-linux -ccc-clang-archs mipsel -S -o - -emit-llvm %s // This checks that the frontend will accept inline asm constraints // c', 'l' and 'x'. Semantic checking will happen in the // llvm backend. Any bad constraint letters will cause the frontend to // error out. int main() { // 'c': 16 bit address register for Mips16, GPR for all others // I am using 'c' to constrain both the target and one of the source // registers. We are looking for syntactical correctness. int __s, __v = 17; int __t; __asm__ __volatile__( "addi %0,%1,%2 \n\t\t" : "=c" (__t) : "c" (__s), "I" (__v)); // 'l': lo register // We are making it clear that destination register is lo with the // use of the 'l' constraint ("=l"). int i_temp = 44; int i_result; __asm__ __volatile__( "mtlo %1 \n\t\t" : "=l" (i_result) : "r" (i_temp) : "lo"); // 'x': Combined lo/hi registers // We are specifying that destination registers are the hi/lo pair with the // use of the 'x' constraint ("=x"). int i_hi = 3; int i_lo = 2; long long ll_result = 0; __asm__ __volatile__( "mthi %1 \n\t\t" "mtlo %2 \n\t\t" : "=x" (ll_result) : "r" (i_hi), "r" (i_lo) : ); return 0; }