[compiler-rt] [compiler-rt][ARM] Add missing PACBTI support to assembly aeabi functions (PR #142400)

[Peter Smith via llvm-commits]

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@@ -37,23 +42,34 @@ DEFINE_COMPILERRT_FUNCTION(__aeabi_cfcmpeq)
         movs r0, #0xF
         lsls r0, r0, #31
         pop {r0-r3, pc}
+#else
+#if defined(__ARM_FEATURE_PAC_DEFAULT)
+        pop {r0-r3, r12, lr}
+        beq 2f
+        aut r12, lr, sp
+        b __aeabi_cfcmple
 #else
         pop {r0-r3, lr}
-
         // NaN has been ruled out, so __aeabi_cfcmple can't trap
         // Use "it ne" + unconditional branch to guarantee a supported relocation if
         // __aeabi_cfcmple is in a different section for some builds.
         IT(ne)
         bne __aeabi_cfcmple
+#endif
 
+2:
 #if defined(USE_THUMB_2)
-        mov ip, #APSR_C
-        msr APSR_nzcvq, ip
+        mov r0, #APSR_C
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smithp35 wrote:

Same comment about not corrupting r0 due to the custom procedure calling standard.

https://github.com/llvm/llvm-project/pull/142400