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authorQingfang Deng <qingfang.deng@siflower.com.cn>2024-05-27 17:24:04 +0800
committerPalmer Dabbelt <palmer@rivosinc.com>2024-07-15 08:46:46 -0700
commit93b63f68d00a0483b450b446e2ea5386a1b94213 (patch)
treeb5ac3c7e325e2c94a7eb7151e44060792a970736
parentriscv: set trap vector earlier (diff)
downloadwireguard-linux-93b63f68d00a0483b450b446e2ea5386a1b94213.tar.xz
wireguard-linux-93b63f68d00a0483b450b446e2ea5386a1b94213.zip
riscv: lib: relax assembly constraints in hweight
rd and rs don't have to be the same. In some cases where rs needs to be saved for later usage, this will save us some mv instructions. Signed-off-by: Qingfang Deng <qingfang.deng@siflower.com.cn> Reviewed-by: Xiao Wang <xiao.w.wang@intel.com> Link: https://lore.kernel.org/r/20240527092405.134967-1-dqfext@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
-rw-r--r--arch/riscv/include/asm/arch_hweight.h8
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/riscv/include/asm/arch_hweight.h b/arch/riscv/include/asm/arch_hweight.h
index 85b2c443823e..613769b9cdc9 100644
--- a/arch/riscv/include/asm/arch_hweight.h
+++ b/arch/riscv/include/asm/arch_hweight.h
@@ -26,9 +26,9 @@ static __always_inline unsigned int __arch_hweight32(unsigned int w)
asm (".option push\n"
".option arch,+zbb\n"
- CPOPW "%0, %0\n"
+ CPOPW "%0, %1\n"
".option pop\n"
- : "+r" (w) : :);
+ : "=r" (w) : "r" (w) :);
return w;
@@ -57,9 +57,9 @@ static __always_inline unsigned long __arch_hweight64(__u64 w)
asm (".option push\n"
".option arch,+zbb\n"
- "cpop %0, %0\n"
+ "cpop %0, %1\n"
".option pop\n"
- : "+r" (w) : :);
+ : "=r" (w) : "r" (w) :);
return w;