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| author | Peter Bergner <bergner@linux.ibm.com> | 2024-11-05 16:05:53 -0600 |
|---|---|---|
| committer | Peter Bergner <bergner@linux.ibm.com> | 2024-11-19 12:43:57 -0500 |
| commit | 229265cc2c1d03d8ee4a55cf73b1fe63b210bdf0 (patch) | |
| tree | 2a617db826fc327987e8fb100c2c9b3f3a8dacca | |
| parent | 7f045c0b48633b198b42bebdff0024d7cfab3901 (diff) | |
| download | glibc-229265cc2c1d03d8ee4a55cf73b1fe63b210bdf0.tar.gz glibc-229265cc2c1d03d8ee4a55cf73b1fe63b210bdf0.tar.xz glibc-229265cc2c1d03d8ee4a55cf73b1fe63b210bdf0.zip | |
powerpc: Improve the inline asm for syscall wrappers
Update the inline asm syscall wrappers to match the newer register constraint usage in INTERNAL_VSYSCALL_CALL_TYPE. Use the faster mfocrf instruction when available, rather than the slower mfcr microcoded instruction.
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/sysdep.h | 42 |
1 files changed, 22 insertions, 20 deletions
diff --git a/sysdeps/unix/sysv/linux/powerpc/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/sysdep.h index 48f3d0d1b2..62b77a79f0 100644 --- a/sysdeps/unix/sysv/linux/powerpc/sysdep.h +++ b/sysdeps/unix/sysv/linux/powerpc/sysdep.h @@ -32,6 +32,18 @@ #undef SYS_ify #define SYS_ify(syscall_name) __NR_##syscall_name +#define tostring(s) #s +#define stringify(s) tostring(s) + +#ifdef _ARCH_PWR4 +/* Power4 and later cpus introduced a faster instruction to copy one + CR field, rather than the slower microcoded mfcr which copies all + CR fields. */ +# define MFCR0(REG) "mfocrf " stringify(REG) ",0x80" +#else +# define MFCR0(REG) "mfcr " stringify(REG) +#endif + /* Define a macro which expands inline into the wrapper code for a system call. This use is for internal calls that do not need to handle errors normally. It will never touch errno. This returns just what the kernel @@ -52,7 +64,7 @@ __asm__ __volatile__ \ ("mtctr %0\n\t" \ "bctrl\n\t" \ - "mfcr %0\n\t" \ + MFCR0(%0) "\n\t" \ "0:" \ : "+r" (r0), "+r" (r3), "+r" (r4), "+r" (r5), "+r" (r6), \ "+r" (r7), "+r" (r8) \ @@ -83,11 +95,10 @@ "scv 0\n\t" \ ".machine \"pop\"\n\t" \ "0:" \ - : "=&r" (r0), \ - "=&r" (r3), "=&r" (r4), "=&r" (r5), \ - "=&r" (r6), "=&r" (r7), "=&r" (r8) \ - : ASM_INPUT_##nr \ - : "r9", "r10", "r11", "r12", \ + : "+r" (r0), \ + "+r" (r3), "+r" (r4), "+r" (r5), \ + "+r" (r6), "+r" (r7), "+r" (r8) \ + : : "r9", "r10", "r11", "r12", \ "cr0", "cr1", "cr5", "cr6", "cr7", \ "xer", "lr", "ctr", "memory"); \ r3; \ @@ -97,13 +108,12 @@ ({ \ __asm__ __volatile__ \ ("sc\n\t" \ - "mfcr %0\n\t" \ + MFCR0(%0) "\n\t" \ "0:" \ - : "=&r" (r0), \ - "=&r" (r3), "=&r" (r4), "=&r" (r5), \ - "=&r" (r6), "=&r" (r7), "=&r" (r8) \ - : ASM_INPUT_##nr \ - : "r9", "r10", "r11", "r12", \ + : "+r" (r0), \ + "+r" (r3), "+r" (r4), "+r" (r5), \ + "+r" (r6), "+r" (r7), "+r" (r8) \ + : : "r9", "r10", "r11", "r12", \ "xer", "cr0", "ctr", "memory"); \ r0 & (1 << 28) ? -r3 : r3; \ }) @@ -199,14 +209,6 @@ __illegally_sized_syscall_arg6 (); \ r8 = _arg6 -#define ASM_INPUT_0 "0" (r0) -#define ASM_INPUT_1 ASM_INPUT_0, "1" (r3) -#define ASM_INPUT_2 ASM_INPUT_1, "2" (r4) -#define ASM_INPUT_3 ASM_INPUT_2, "3" (r5) -#define ASM_INPUT_4 ASM_INPUT_3, "4" (r6) -#define ASM_INPUT_5 ASM_INPUT_4, "5" (r7) -#define ASM_INPUT_6 ASM_INPUT_5, "6" (r8) - /* List of system calls which are supported as vsyscalls. */ #define VDSO_NAME "LINUX_2.6.15" #define VDSO_HASH 123718565 |