[llvm] [RuntimeDyldChecker][AArch32] Add a PC offset to next_PC for ARM targets (PR #91746)
Eymen Ünay via llvm-commits
llvm-commits at lists.llvm.org
Sun May 12 02:52:50 PDT 2024
https://github.com/eymay updated https://github.com/llvm/llvm-project/pull/91746
>From df8308894fbe40d28af4625164c28e1e314c394a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eymen=20=C3=9Cnay?= <eymenunay at outlook.com>
Date: Fri, 10 May 2024 16:42:57 +0300
Subject: [PATCH 1/2] [RuntimeDyldChecker][AArch32] Add a PC offset to next_PC
for ARM targets
In ARM mode, the Program Counter (PC) points to the current instruction's
address + 8 instead of + 4. This offset is added to RuntimeDyldChecker to
use `next_pc` expression in JITLink tests.
---
.../RuntimeDyld/RuntimeDyldChecker.cpp | 14 +++++++++++++-
.../JITLink/AArch32/ELF_relocations_arm.s | 6 ++----
.../JITLink/AArch32/ELF_relocations_thumbv6m.s | 2 +-
3 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp
index 11fb21a9c1c0a..dcbe3f1712db5 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp
@@ -369,7 +369,19 @@ class RuntimeDyldCheckerExprEval {
uint64_t SymbolAddr = PCtx.IsInsideLoad
? Checker.getSymbolLocalAddr(Symbol)
: Checker.getSymbolRemoteAddr(Symbol);
- uint64_t NextPC = SymbolAddr + InstSize;
+
+ uint64_t PCOffset = 0;
+ auto TT = Checker.getTripleForSymbol(Checker.getTargetFlag(Symbol));
+ switch (TT.getArch()) {
+ case Triple::ArchType::arm:
+ // ARM mode adds an offset of 4 bytes to PC
+ PCOffset = 4;
+ break;
+ default:
+ PCOffset = 0;
+ }
+
+ uint64_t NextPC = SymbolAddr + InstSize + PCOffset;
return std::make_pair(EvalResult(NextPC), RemainingExpr);
}
diff --git a/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_arm.s b/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_arm.s
index 3dec8c96f5cd5..4d12b84d48c91 100644
--- a/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_arm.s
+++ b/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_arm.s
@@ -28,9 +28,7 @@
# CHECK-INSTR: 4: ebfffffe bl
# CHECK-INSTR: 0000000c <call_target_arm>
# CHECK-INSTR: 00000010 <call_target_thumb>
-# ARM branch offset is 8, because it accounts for an additional prefetch
-# instruction that increments PC even though it is implicit
-# jitlink-check: decode_operand(call_site + 0, 0) = call_target_arm - (call_site + 8)
+# 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)
.globl call_site
.type call_site,%function
@@ -62,7 +60,7 @@ call_target_thumb:
# CHECK-INSTR: 00000014 <jump24_site>:
# CHECK-INSTR: 14: eafffffe b
# CHECK-INSTR: 00000018 <jump24_target>
-# jitlink-check: decode_operand(jump24_site, 0) = jump24_target - (jump24_site + 8)
+# jitlink-check: decode_operand(jump24_site, 0) = jump24_target - next_pc(jump24_site)
.globl jump24_site
.type jump24_site,%function
.p2align 2
diff --git a/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_thumbv6m.s b/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_thumbv6m.s
index e0a224d9c7106..9f46ff0ed3922 100644
--- a/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_thumbv6m.s
+++ b/llvm/test/ExecutionEngine/JITLink/AArch32/ELF_relocations_thumbv6m.s
@@ -30,7 +30,7 @@
# CHECK-INSTR: f7ff fffe bl
# We decode the operand with index 2, because bl generates two leading implicit
# predicate operands that we have to skip in order to decode the call_target operand
-# jitlink-check: decode_operand(call_site, 2) = call_target_thumb - (call_site + 4)
+# jitlink-check: decode_operand(call_site, 2) = call_target_thumb - next_pc(call_site)
.globl call_site
.type call_site,%function
.p2align 1
>From 0eecc0ab808b592ccd41aadc32b91a55d9f177d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eymen=20=C3=9Cnay?= <eymenunay at outlook.com>
Date: Sun, 12 May 2024 12:52:14 +0300
Subject: [PATCH 2/2] Simplify the PC offset declaration
---
.../RuntimeDyld/RuntimeDyldChecker.cpp | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp
index dcbe3f1712db5..14c8577aab9d7 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldChecker.cpp
@@ -370,16 +370,9 @@ class RuntimeDyldCheckerExprEval {
? Checker.getSymbolLocalAddr(Symbol)
: Checker.getSymbolRemoteAddr(Symbol);
- uint64_t PCOffset = 0;
+ // ARM mode adds an offset of 4 bytes to PC
auto TT = Checker.getTripleForSymbol(Checker.getTargetFlag(Symbol));
- switch (TT.getArch()) {
- case Triple::ArchType::arm:
- // ARM mode adds an offset of 4 bytes to PC
- PCOffset = 4;
- break;
- default:
- PCOffset = 0;
- }
+ uint64_t PCOffset = TT.getArch() == Triple::ArchType::arm ? 4 : 0;
uint64_t NextPC = SymbolAddr + InstSize + PCOffset;
More information about the llvm-commits
mailing list