Add compiler-rt patch for RHEL 8 page sizes

RHEL 8 uses different page sizes, and we need to patch the CFI
implementation to use those.

0001-Fix-page-size-constant-on-aarch64-and-ppc64le.patch

@@ -0,0 +1,25 @@
+From 5f73befe5a0df82e455f4b1052e62f34009e98bb Mon Sep 17 00:00:00 2001
+From: Tom Stellard <tstellar@redhat.com>
+Date: Tue, 23 Apr 2024 15:08:34 -0700
+Subject: [PATCH] Fix page size constant on aarch64 and ppc64le
+
+---
+ compiler-rt/lib/cfi/cfi.cpp | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/compiler-rt/lib/cfi/cfi.cpp b/compiler-rt/lib/cfi/cfi.cpp
+index ad1c91623514..e7e86e5807a8 100644
+--- a/compiler-rt/lib/cfi/cfi.cpp
++++ b/compiler-rt/lib/cfi/cfi.cpp
+@@ -53,6 +53,8 @@ namespace __cfi {
+ 
+ #if SANITIZER_LOONGARCH64
+ #define kCfiShadowLimitsStorageSize 16384 // 16KiB on loongarch64 per page
++#elif defined(__aarch64__) || defined(__powerpc64__)
++#define kCfiShadowLimitsStorageSize 65536 // 1 page
+ #else
+ #define kCfiShadowLimitsStorageSize 4096 // 1 page
+ #endif
+-- 
+2.40.1
+

llvm.spec

@@ -73,6 +73,9 @@ Patch3002: 0001-Always-build-shared-libs-for-LLD.patch
 #region RHEL patches
 # All RHEL
 Patch9001: 0001-Remove-myst_parser-dependency-for-RHEL.patch
+
+# RHEL 8 only
+Patch9002: 0001-Fix-page-size-constant-on-aarch64-and-ppc64le.patch
 #endregion
 
 %if 0%{?rhel} == 8

prep.spec.inc

@@ -16,6 +16,10 @@
 
 %if %{defined rhel}
 %patch -p1 -P9001
+
+%if %{rhel} == 8
+%patch -p1 -P9002
+%endif
 %endif
 
 #region LLVM preparation