Teach evalNextPC to decode addition expression with a symbol

Author: eymay

llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp

@@ -354,21 +354,41 @@ class RuntimeDyldCheckerExprEval {
           EvalResult(("Cannot decode unknown symbol '" + Symbol + "'").str()),
           "");
 
+    // if there is an offset number expr
+    int64_t SymbolOffset = 0;
+    BinOpToken BinOp;
+    std::tie(BinOp, RemainingExpr) = parseBinOpToken(RemainingExpr);
+    switch (BinOp) {
+    case BinOpToken::Add: {
+      EvalResult Number;
+      std::tie(Number, RemainingExpr) = evalNumberExpr(RemainingExpr);
+      SymbolOffset = Number.getValue();
+      break;
+    }
+    case BinOpToken::Invalid:
+      break;
+    default:
+      return std::make_pair(
+          unexpectedToken(RemainingExpr, RemainingExpr,
+                          "expected '+' for offset or ')' if no offset"),
+          "");
+    }
+
     if (!RemainingExpr.starts_with(")"))
       return std::make_pair(
           unexpectedToken(RemainingExpr, RemainingExpr, "expected ')'"), "");
     RemainingExpr = RemainingExpr.substr(1).ltrim();
 
     MCInst Inst;
     uint64_t InstSize;
-    if (!decodeInst(Symbol, Inst, InstSize, 0))
+    if (!decodeInst(Symbol, Inst, InstSize, SymbolOffset))
       return std::make_pair(
           EvalResult(("Couldn't decode instruction at '" + Symbol + "'").str()),
           "");
 
-    uint64_t SymbolAddr = PCtx.IsInsideLoad
-                              ? Checker.getSymbolLocalAddr(Symbol)
-                              : Checker.getSymbolRemoteAddr(Symbol);
+    uint64_t SymbolAddr =
+        PCtx.IsInsideLoad ? Checker.getSymbolLocalAddr(Symbol)
+                          : Checker.getSymbolRemoteAddr(Symbol) + SymbolOffset;
 
     // ARM mode adds an offset of 4 bytes to PC
     auto TT = Checker.getTripleForSymbol(Checker.getTargetFlag(Symbol));

llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_arm.s

@@ -29,7 +29,7 @@
 # CHECK-INSTR: 	0000000c <call_target_arm>
 # CHECK-INSTR: 	00000010 <call_target_thumb>
 # jitlink-check: decode_operand(call_site + 0, 0) = call_target_arm   - next_pc(call_site)
-# jitlink-check: decode_operand(call_site + 4, 0) = call_target_thumb - (call_site + 12)
+# jitlink-check: decode_operand(call_site + 4, 0) = call_target_thumb - next_pc(call_site + 4)
 	.globl	call_site
 	.type	call_site,%function
 	.p2align	2

llvm/test/ExecutionEngine/JITLink/AArch32/ELF_stubs_arm.s

@@ -27,7 +27,7 @@
 # hard-code it in the immediate field.
 
 # The external function ext will return to the caller directly.
-# jitlink-check: decode_operand(test_arm_jump, 0) = stub_addr(out.o, ext) - (test_arm_jump + 8)
+# jitlink-check: decode_operand(test_arm_jump, 0) = stub_addr(out.o, ext) - next_pc(test_arm_jump)
 	.globl	test_arm_jump
 	.type	test_arm_jump,%function
 	.p2align	2
@@ -38,7 +38,7 @@ test_arm_jump:
 # The branch-with-link sets the LR register so that the external function ext
 # returns to us. We have to save the register (push) and return to main manually
 # (pop). This adds the +4 offset for the bl instruction we decode:
-# jitlink-check: decode_operand(test_arm_call + 4, 0) = stub_addr(out.o, ext) - (test_arm_call + 8) - 4
+# jitlink-check: decode_operand(test_arm_call + 4, 0) = stub_addr(out.o, ext) - next_pc(test_arm_call) - 4
 	.globl  test_arm_call
 	.type	test_arm_call,%function
 	.p2align	2

llvm/test/ExecutionEngine/JITLink/AArch32/ELF_stubs_multi.s

@@ -13,7 +13,7 @@
 # ascending size (because the default memory manager lays out blocks by size).
 
 # Thumb relocation site emits thumb stub
-# jitlink-check: decode_operand(test_stub_thumb, 0) = stub_addr(out.o, ext, thumb) - (test_stub_thumb + 4)
+# jitlink-check: decode_operand(test_stub_thumb, 0) = stub_addr(out.o, ext, thumb) - next_pc(test_stub_thumb)
 	.globl  test_stub_thumb
 	.type	test_stub_thumb,%function
 	.p2align	1
@@ -24,7 +24,7 @@ test_stub_thumb:
 	.size	test_stub_thumb, .-test_stub_thumb
 
 # Arm relocation site emits arm stub
-# jitlink-check: decode_operand(test_stub_arm, 0) = stub_addr(out.o, ext, arm) - (test_stub_arm + 8)
+# jitlink-check: decode_operand(test_stub_arm, 0) = stub_addr(out.o, ext, arm) - next_pc(test_stub_arm)
 	.globl  test_stub_arm
 	.type	test_stub_arm,%function
 	.p2align	2