Merge #3021

3021: Added back some needed relocation for arm64 llvm compiler r=epilys a=ptitSeb # Description Add back missing Aarch64 relocations (needed for llvm compiler) Co-authored-by: ptitSeb <[email protected]>
wasmerio · Jul 20, 2022 · e75e76d · e75e76d
2 parents 8f1a401 + fec2e5f
commit e75e76d
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Showing 3 changed files with 61 additions and 1 deletion.
diff --git a/lib/compiler-llvm/src/object_file.rs b/lib/compiler-llvm/src/object_file.rs
@@ -172,6 +172,26 @@ where
                 (object::Architecture::Aarch64, object::RelocationKind::PltRelative, 26) => {
                     RelocationKind::Arm64Call
                 }
+                (
+                    object::Architecture::Aarch64,
+                    object::RelocationKind::Elf(object::elf::R_AARCH64_MOVW_UABS_G0_NC),
+                    0,
+                ) => RelocationKind::Arm64Movw0,
+                (
+                    object::Architecture::Aarch64,
+                    object::RelocationKind::Elf(object::elf::R_AARCH64_MOVW_UABS_G1_NC),
+                    0,
+                ) => RelocationKind::Arm64Movw1,
+                (
+                    object::Architecture::Aarch64,
+                    object::RelocationKind::Elf(object::elf::R_AARCH64_MOVW_UABS_G2_NC),
+                    0,
+                ) => RelocationKind::Arm64Movw2,
+                (
+                    object::Architecture::Aarch64,
+                    object::RelocationKind::Elf(object::elf::R_AARCH64_MOVW_UABS_G3),
+                    0,
+                ) => RelocationKind::Arm64Movw3,
                 _ => {
                     return Err(CompileError::Codegen(format!(
                         "unknown relocation {:?}",

diff --git a/lib/compiler/src/engine/universal/link.rs b/lib/compiler/src/engine/universal/link.rs
@@ -69,6 +69,30 @@ fn apply_relocation(
                 | (read_unaligned(reloc_address as *mut u32) & 0xfc00_0000);
             write_unaligned(reloc_address as *mut u32, reloc_delta);
         },
+        RelocationKind::Arm64Movw0 => unsafe {
+            let (reloc_address, reloc_delta) = r.for_address(body, target_func_address as u64);
+            let reloc_delta =
+                (((reloc_delta & 0xffff) as u32) << 5) | read_unaligned(reloc_address as *mut u32);
+            write_unaligned(reloc_address as *mut u32, reloc_delta);
+        },
+        RelocationKind::Arm64Movw1 => unsafe {
+            let (reloc_address, reloc_delta) = r.for_address(body, target_func_address as u64);
+            let reloc_delta = ((((reloc_delta >> 16) & 0xffff) as u32) << 5)
+                | read_unaligned(reloc_address as *mut u32);
+            write_unaligned(reloc_address as *mut u32, reloc_delta);
+        },
+        RelocationKind::Arm64Movw2 => unsafe {
+            let (reloc_address, reloc_delta) = r.for_address(body, target_func_address as u64);
+            let reloc_delta = ((((reloc_delta >> 32) & 0xffff) as u32) << 5)
+                | read_unaligned(reloc_address as *mut u32);
+            write_unaligned(reloc_address as *mut u32, reloc_delta);
+        },
+        RelocationKind::Arm64Movw3 => unsafe {
+            let (reloc_address, reloc_delta) = r.for_address(body, target_func_address as u64);
+            let reloc_delta = ((((reloc_delta >> 48) & 0xffff) as u32) << 5)
+                | read_unaligned(reloc_address as *mut u32);
+            write_unaligned(reloc_address as *mut u32, reloc_delta);
+        },
         kind => panic!(
             "Relocation kind unsupported in the current architecture {}",
             kind

diff --git a/lib/types/src/compilation/relocation.rs b/lib/types/src/compilation/relocation.rs
@@ -41,6 +41,14 @@ pub enum RelocationKind {
     Arm32Call,
     /// Arm64 call target
     Arm64Call,
+    /// Arm64 movk/z part 0
+    Arm64Movw0,
+    /// Arm64 movk/z part 1
+    Arm64Movw1,
+    /// Arm64 movk/z part 2
+    Arm64Movw2,
+    /// Arm64 movk/z part 3
+    Arm64Movw3,
     // /// RISC-V call target
     // RiscvCall,
     /// Elf x86_64 32 bit signed PC relative offset to two GOT entries for GD symbol.
@@ -62,6 +70,10 @@ impl fmt::Display for RelocationKind {
             Self::X86CallPLTRel4 => write!(f, "CallPLTRel4"),
             Self::X86GOTPCRel4 => write!(f, "GOTPCRel4"),
             Self::Arm32Call | Self::Arm64Call => write!(f, "Call"),
+            Self::Arm64Movw0 => write!(f, "Arm64MovwG0"),
+            Self::Arm64Movw1 => write!(f, "Arm64MovwG1"),
+            Self::Arm64Movw2 => write!(f, "Arm64MovwG2"),
+            Self::Arm64Movw3 => write!(f, "Arm64MovwG3"),
             Self::ElfX86_64TlsGd => write!(f, "ElfX86_64TlsGd"),
             // Self::MachOX86_64Tlv => write!(f, "MachOX86_64Tlv"),
         }
@@ -101,7 +113,11 @@ impl Relocation {
     /// The function returns the relocation address and the delta.
     pub fn for_address(&self, start: usize, target_func_address: u64) -> (usize, u64) {
         match self.kind {
-            RelocationKind::Abs8 => {
+            RelocationKind::Abs8
+            | RelocationKind::Arm64Movw0
+            | RelocationKind::Arm64Movw1
+            | RelocationKind::Arm64Movw2
+            | RelocationKind::Arm64Movw3 => {
                 let reloc_address = start + self.offset as usize;
                 let reloc_addend = self.addend as isize;
                 let reloc_abs = target_func_address