c18n: Remove assembly wrappers for _rtld_{setjmp,longjmp,unw_*}

Instead, use the get_trusted_frame macro to obtain the trusted frame in C.
CTSRD-CHERI · Mar 26, 2024 · 8d29f2c · 8d29f2c
1 parent 716966f
commit 8d29f2c
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Showing 4 changed files with 84 additions and 203 deletions.
diff --git a/lib/libc/aarch64/gen/_setjmp.S b/lib/libc/aarch64/gen/_setjmp.S
@@ -82,7 +82,7 @@ ENTRY(_longjmp)
 	/* Restore the stack pointer */
 	ldr	REG(8), [REG(0)], #(REG_WIDTH)
 #if defined(__CHERI_PURE_CAPABILITY__) && defined(RTLD_SANDBOX)
-	mov	c3, c8
+	mov	c2, c8
 #else
 	mov	REGN(sp), REG(8)
 #endif
@@ -105,12 +105,11 @@ ENTRY(_longjmp)
 
 	/* Load the return value */
 #if defined(__CHERI_PURE_CAPABILITY__) && defined(RTLD_SANDBOX)
-	mov	c4, c0
+	mov	c3, c0
 #endif
 	cmp	x1, #0
 	csinc	x0, x1, xzr, ne
 #if defined(__CHERI_PURE_CAPABILITY__) && defined(RTLD_SANDBOX)
-	mov	c1, c4
 	/*
 	 * Tail-call to restore Executive mode state
 	 */

diff --git a/lib/libc/aarch64/gen/setjmp.S b/lib/libc/aarch64/gen/setjmp.S
@@ -111,7 +111,7 @@ ENTRY(longjmp)
 	/* Restore the stack pointer */
 	ldr	REG(8), [REG(0)], #(REG_WIDTH)
 #if defined(__CHERI_PURE_CAPABILITY__) && defined(RTLD_SANDBOX)
-	mov	c3, c8
+	mov	c2, c8
 #else
 	mov	REGN(sp), REG(8)
 #endif
@@ -132,12 +132,11 @@ ENTRY(longjmp)
 
 	/* Load the return value */
 #if defined(__CHERI_PURE_CAPABILITY__) && defined(RTLD_SANDBOX)
-	mov	c4, c0
+	mov	c3, c0
 #endif
 	cmp	x1, #0
 	csinc	x0, x1, xzr, ne
 #if defined(__CHERI_PURE_CAPABILITY__) && defined(RTLD_SANDBOX)
-	mov	c1, c4
 	/*
 	 * Tail-call to restore Executive mode state
 	 */

diff --git a/libexec/rtld-elf/aarch64/rtld_c18n_asm.S b/libexec/rtld-elf/aarch64/rtld_c18n_asm.S
@@ -30,32 +30,6 @@
 #include "rtld_c18n_machdep.h"
 #undef IN_ASM
 
-ENTRY(_rtld_setjmp)
-#ifdef __ARM_MORELLO_PURECAP_BENCHMARK_ABI
-	mrs	c2, rcsp_el0
-#else
-	mov	c2, csp
-#endif
-	/*
-	 * This function MUST preserve the value of c0 and clear unused return
-	 * value registers.
-	 */
-	b	_rtld_setjmp_impl
-END(_rtld_setjmp)
-
-ENTRY(_rtld_longjmp)
-#ifdef __ARM_MORELLO_PURECAP_BENCHMARK_ABI
-	mrs	c2, rcsp_el0
-#else
-	mov	c2, csp
-#endif
-	/*
-	 * This function MUST preserve the value of c0 and clear unused return
-	 * value registers.
-	 */
-	b	_rtld_longjmp_impl
-END(_rtld_longjmp)
-
 ENTRY(_rtld_thread_start)
 	mov	c1, csp
 	sub	csp, csp, #(CAP_WIDTH * 2)
@@ -304,54 +278,6 @@ ENTRY(tramp_hook)
 #endif
 END(tramp_hook)
 
-ENTRY(_rtld_unw_getcontext)
-	/*
-	 * This function MUST preserve the value of c0.
-	 */
-#ifdef __ARM_MORELLO_PURECAP_BENCHMARK_ABI
-	mrs	c2, rcsp_el0
-#else
-	mov	c2, csp
-#endif
-	b	_rtld_unw_getcontext_impl
-END(_rtld_unw_getcontext)
-
-ENTRY(_rtld_unw_setcontext)
-	/*
-	 * This function MUST preserve the value of c0, c1.
-	 */
-#ifdef __ARM_MORELLO_PURECAP_BENCHMARK_ABI
-	mrs	c2, rcsp_el0
-#else
-	mov	c2, csp
-#endif
-	b	_rtld_unw_resume
-END(_rtld_unw_setcontext)
-
-ENTRY(_rtld_unw_getcontext_unsealed)
-	/*
-	 * This function MUST preserve the value of c0.
-	 */
-#ifdef __ARM_MORELLO_PURECAP_BENCHMARK_ABI
-	mrs	c2, rcsp_el0
-#else
-	mov	c2, csp
-#endif
-	b	_rtld_unw_getcontext_impl_unsealed
-END(_rtld_unw_getcontext)
-
-ENTRY(_rtld_unw_setcontext_unsealed)
-	/*
-	 * This function MUST preserve the value of c0, c1.
-	 */
-#ifdef __ARM_MORELLO_PURECAP_BENCHMARK_ABI
-	mrs	c2, rcsp_el0
-#else
-	mov	c2, csp
-#endif
-	b	_rtld_unw_resume_unsealed
-END(_rtld_unw_setcontext)
-
 /*
  * Trampoline templates are code but reside in rodata. Hence a new macro is
  * defined to describe them.