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Re: [PATCH 1/3] aarch64: Clean up _dl_runtime_resolve

On 01/08/18 23:23, wrote:
From: Richard Henderson <>

	* sysdeps/aarch64/dl-trampoline.S (_dl_runtime_resolve):
	Do not record unwind info for arguments; this is unneeded;
	do not save x9 just to have a register to pair with x8;
	properly include the 16 bytes of PLT stack into the unwind;
	create a frame pointer with the spare stack slot;
	rearrange the exit to only adjust the stack once.

i thought the cfi annotations were needed for all registers
in case the debugger wants to investigate register content
across a _dl_runtime_resolve frame (possibly several frames
up in the call stack), this may not be a common use case though
and i don't know what's the convention in glibc asm, the compiler
seems to emit annotation for all spilled registers with -g.

--- a/sysdeps/aarch64/dl-trampoline.S
+++ b/sysdeps/aarch64/dl-trampoline.S
@@ -32,7 +32,6 @@
  	.globl _dl_runtime_resolve
  	.type _dl_runtime_resolve, #function
-	cfi_startproc
  	.align 2
  	/* AArch64 we get called with:
@@ -41,46 +40,24 @@ _dl_runtime_resolve:
  	   [sp, #8]	lr
  	   [sp, #0]	&PLTGOT[n]
+	cfi_startproc

is there a problem keeping it at its original place above?
the tlsdesc asm has cfi_startproc at the same place.

otherwise the patch looks ok.

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