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author | Kyrylo Tkachov <kyrylo.tkachov@arm.com> | 2021-03-17 18:21:05 +0000 |
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committer | Kyrylo Tkachov <kyrylo.tkachov@arm.com> | 2021-03-17 18:21:05 +0000 |
commit | f7581eb38eeaa8af64f3cdfe2faf764f5883f16f (patch) | |
tree | d4eea38c38257195c866a5b645ee3f31481efdc8 | |
parent | adf14bdbc10d4114865a08cf20020a2616039057 (diff) | |
download | gcc-f7581eb38eeaa8af64f3cdfe2faf764f5883f16f.zip gcc-f7581eb38eeaa8af64f3cdfe2faf764f5883f16f.tar.gz gcc-f7581eb38eeaa8af64f3cdfe2faf764f5883f16f.tar.bz2 |
aarch64: Fix status return logic in RNG intrinsics
There is a bug with the RNG intrinsics in their return code. The definition says:
"Stores a 64-bit random number into the object pointed to by the argument and returns zero.
If the implementation could not generate a random number within a reasonable period of time
the object pointed to by the input is set to zero and a non-zero value is returned."
This means we should be testing whether to return non-zero with:
CSET W0, EQ
rather than NE.
This patch fixes that.
gcc/ChangeLog:
* config/aarch64/aarch64-builtins.c (aarch64_expand_rng_builtin): Use EQ
to compare against CC_REG rather than NE.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/acle/rng_2.c: New test.
-rw-r--r-- | gcc/config/aarch64/aarch64-builtins.c | 2 | ||||
-rw-r--r-- | gcc/testsuite/gcc.target/aarch64/acle/rng_2.c | 12 |
2 files changed, 13 insertions, 1 deletions
diff --git a/gcc/config/aarch64/aarch64-builtins.c b/gcc/config/aarch64/aarch64-builtins.c index 25ab866..acdea2a 100644 --- a/gcc/config/aarch64/aarch64-builtins.c +++ b/gcc/config/aarch64/aarch64-builtins.c @@ -1954,7 +1954,7 @@ aarch64_expand_rng_builtin (tree exp, rtx target, int fcode, int ignore) return target; rtx cc_reg = gen_rtx_REG (CC_Zmode, CC_REGNUM); - rtx cmp_rtx = gen_rtx_fmt_ee (NE, SImode, cc_reg, const0_rtx); + rtx cmp_rtx = gen_rtx_fmt_ee (EQ, SImode, cc_reg, const0_rtx); emit_insn (gen_aarch64_cstoresi (target, cmp_rtx, cc_reg)); return target; } diff --git a/gcc/testsuite/gcc.target/aarch64/acle/rng_2.c b/gcc/testsuite/gcc.target/aarch64/acle/rng_2.c new file mode 100644 index 0000000..206136c --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/acle/rng_2.c @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -march=armv8.5-a+rng" } */ + +#include <arm_acle.h> + +int test_rndr (uint64_t *addr) +{ + return __rndr (addr); +} + +/* { dg-final { scan-assembler-times {cset\t...?, eq} 1 } } */ + |