[llvm] [JITLink][LoongArch] Add R_LARCH_{B16, B21} relocations support (PR #121096)
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Wed Dec 25 01:17:04 PST 2024
https://github.com/zhaoqi5 created https://github.com/llvm/llvm-project/pull/121096
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>From 6dc8812df1727afd8246ae91a17bf88ca70426d6 Mon Sep 17 00:00:00 2001
From: Qi Zhao <zhaoqi01 at loongson.cn>
Date: Wed, 25 Dec 2024 17:01:35 +0800
Subject: [PATCH] [JITLink][LoongArch] Add R_LARCH_{B16,B21} relocations
support
---
.../llvm/ExecutionEngine/JITLink/loongarch.h | 75 +++++++++++++++++++
.../ExecutionEngine/JITLink/ELF_loongarch.cpp | 4 +
.../lib/ExecutionEngine/JITLink/loongarch.cpp | 2 +
.../LoongArch/ELF_loongarch32_relocations.s | 24 ++++++
.../LoongArch/ELF_loongarch64_relocations.s | 26 ++++++-
5 files changed, 130 insertions(+), 1 deletion(-)
diff --git a/llvm/include/llvm/ExecutionEngine/JITLink/loongarch.h b/llvm/include/llvm/ExecutionEngine/JITLink/loongarch.h
index 39a7db32258ce7..d31c749bad1b1c 100644
--- a/llvm/include/llvm/ExecutionEngine/JITLink/loongarch.h
+++ b/llvm/include/llvm/ExecutionEngine/JITLink/loongarch.h
@@ -41,6 +41,50 @@ enum EdgeKind_loongarch : Edge::Kind {
///
Pointer32,
+ /// A 16-bit PC-relative branch.
+ ///
+ /// Represents a PC-relative branch to a target within +/-128Kb. The target
+ /// must be 4-byte aligned.
+ ///
+ /// Fixup expression:
+ /// Fixup <- (Target - Fixup + Addend) >> 2 : int16
+ ///
+ /// Notes:
+ /// The '16' in the name refers to the number operand bits and follows the
+ /// naming convention used by the corresponding ELF relocations. Since the low
+ /// two bits must be zero (because of the 4-byte alignment of the target) the
+ /// operand is effectively a signed 18-bit number.
+ ///
+ /// Errors:
+ /// - The result of the unshifted part of the fixup expression must be
+ /// 4-byte aligned otherwise an alignment error will be returned.
+ /// - The result of the fixup expression must fit into an int16 otherwise an
+ /// out-of-range error will be returned.
+ ///
+ Branch16PCRel,
+
+ /// A 21-bit PC-relative branch.
+ ///
+ /// Represents a PC-relative branch to a target within +/-4Mb. The Target must
+ /// be 4-byte aligned.
+ ///
+ /// Fixup expression:
+ /// Fixup <- (Target - Fixup + Addend) >> 2 : int21
+ ///
+ /// Notes:
+ /// The '21' in the name refers to the number operand bits and follows the
+ /// naming convention used by the corresponding ELF relocations. Since the low
+ /// two bits must be zero (because of the 4-byte alignment of the target) the
+ /// operand is effectively a signed 23-bit number.
+ ///
+ /// Errors:
+ /// - The result of the unshifted part of the fixup expression must be
+ /// 4-byte aligned otherwise an alignment error will be returned.
+ /// - The result of the fixup expression must fit into an int21 otherwise an
+ /// out-of-range error will be returned.
+ ///
+ Branch21PCRel,
+
/// A 26-bit PC-relative branch.
///
/// Represents a PC-relative call or branch to a target within +/-128Mb. The
@@ -213,6 +257,37 @@ inline Error applyFixup(LinkGraph &G, Block &B, const Edge &E) {
*(ulittle32_t *)FixupPtr = Value;
break;
}
+ case Branch16PCRel: {
+ int64_t Value = TargetAddress - FixupAddress + Addend;
+
+ if (!isInt<18>(Value))
+ return makeTargetOutOfRangeError(G, B, E);
+
+ if (!isShiftedInt<16, 2>(Value))
+ return makeAlignmentError(orc::ExecutorAddr(FixupAddress), Value, 4, E);
+
+ uint32_t RawInstr = *(little32_t *)FixupPtr;
+ uint32_t Imm = static_cast<uint32_t>(Value >> 2);
+ uint32_t Imm15_0 = extractBits(Imm, /*Hi=*/15, /*Lo=*/0) << 10;
+ *(little32_t *)FixupPtr = RawInstr | Imm15_0;
+ break;
+ }
+ case Branch21PCRel: {
+ int64_t Value = TargetAddress - FixupAddress + Addend;
+
+ if (!isInt<23>(Value))
+ return makeTargetOutOfRangeError(G, B, E);
+
+ if (!isShiftedInt<21, 2>(Value))
+ return makeAlignmentError(orc::ExecutorAddr(FixupAddress), Value, 4, E);
+
+ uint32_t RawInstr = *(little32_t *)FixupPtr;
+ uint32_t Imm = static_cast<uint32_t>(Value >> 2);
+ uint32_t Imm15_0 = extractBits(Imm, /*Hi=*/15, /*Lo=*/0) << 10;
+ uint32_t Imm20_16 = extractBits(Imm, /*Hi=*/20, /*Lo=*/16);
+ *(little32_t *)FixupPtr = RawInstr | Imm15_0 | Imm20_16;
+ break;
+ }
case Branch26PCRel: {
int64_t Value = TargetAddress - FixupAddress + Addend;
diff --git a/llvm/lib/ExecutionEngine/JITLink/ELF_loongarch.cpp b/llvm/lib/ExecutionEngine/JITLink/ELF_loongarch.cpp
index 56c32aeecf55a8..a12e9f33e80a6b 100644
--- a/llvm/lib/ExecutionEngine/JITLink/ELF_loongarch.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/ELF_loongarch.cpp
@@ -58,6 +58,10 @@ class ELFLinkGraphBuilder_loongarch : public ELFLinkGraphBuilder<ELFT> {
return Pointer32;
case ELF::R_LARCH_32_PCREL:
return Delta32;
+ case ELF::R_LARCH_B16:
+ return Branch16PCRel;
+ case ELF::R_LARCH_B21:
+ return Branch21PCRel;
case ELF::R_LARCH_B26:
return Branch26PCRel;
case ELF::R_LARCH_PCALA_HI20:
diff --git a/llvm/lib/ExecutionEngine/JITLink/loongarch.cpp b/llvm/lib/ExecutionEngine/JITLink/loongarch.cpp
index 010c0ed6713d49..cdb3da04354eee 100644
--- a/llvm/lib/ExecutionEngine/JITLink/loongarch.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/loongarch.cpp
@@ -44,6 +44,8 @@ const char *getEdgeKindName(Edge::Kind K) {
KIND_NAME_CASE(Delta32)
KIND_NAME_CASE(NegDelta32)
KIND_NAME_CASE(Delta64)
+ KIND_NAME_CASE(Branch16PCRel)
+ KIND_NAME_CASE(Branch21PCRel)
KIND_NAME_CASE(Branch26PCRel)
KIND_NAME_CASE(Page20)
KIND_NAME_CASE(PageOffset12)
diff --git a/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch32_relocations.s b/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch32_relocations.s
index 23f6acc307b98f..da9f9982aade7a 100644
--- a/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch32_relocations.s
+++ b/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch32_relocations.s
@@ -103,6 +103,30 @@ test_gotoffset12_external:
ld.w $a0, $a0, %got_pc_lo12(external_data)
.size test_gotoffset12_external, .-test_gotoffset12_external
+## Check R_LARCH_B16 relocation for compare and branch instructions.
+
+# jitlink-check: decode_operand(test_br16, 2)[17:0] = \
+# jitlink-check: (test_br16_target - test_br16)[17:0]
+ .globl test_br16, test_br16_target
+ .p2align 2
+test_br16:
+ beq $t1, $t2, %b16(test_br16_target)
+ .skip (1 << 16)
+test_br16_target:
+ .size test_br16, .-test_br16
+
+## Check R_LARCH_B21 relocation for compare and branch instructions.
+
+# jitlink-check: decode_operand(test_br21, 1)[22:0] = \
+# jitlink-check: (test_br21_target - test_br21)[22:0]
+ .globl test_br21, test_br21_target
+ .p2align 2
+test_br21:
+ beqz $t1, %b21(test_br21_target)
+ .skip (1 << 21)
+test_br21_target:
+ .size test_br21, .-test_br21
+
.globl named_data
.p2align 4
diff --git a/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch64_relocations.s b/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch64_relocations.s
index f07ac5422b8fc8..a390d1b895f798 100644
--- a/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch64_relocations.s
+++ b/llvm/test/ExecutionEngine/JITLink/LoongArch/ELF_loongarch64_relocations.s
@@ -116,7 +116,6 @@ test_gotoffset12_external:
ld.d $a0, $a0, %got_pc_lo12(external_data)
.size test_gotoffset12_external, .-test_gotoffset12_external
-
## Check R_LARCH_CALL36 relocation of a local function call.
# jitlink-check: decode_operand(local_func_call36, 1)[19:0] = \
@@ -130,6 +129,31 @@ local_func_call36:
jirl $ra, $ra, 0
.size local_func_call36, .-local_func_call36
+## Check R_LARCH_B16 relocation for compare and branch instructions.
+
+# jitlink-check: decode_operand(test_br16, 2)[17:0] = \
+# jitlink-check: (test_br16_target - test_br16)[17:0]
+ .globl test_br16, test_br16_target
+ .p2align 2
+test_br16:
+ beq $t1, $t2, %b16(test_br16_target)
+ .skip (1 << 16)
+test_br16_target:
+ .size test_br16, .-test_br16
+
+## Check R_LARCH_B21 relocation for compare and branch instructions.
+
+# jitlink-check: decode_operand(test_br21, 1)[22:0] = \
+# jitlink-check: (test_br21_target - test_br21)[22:0]
+ .globl test_br21, test_br21_target
+ .p2align 2
+test_br21:
+ beqz $t1, %b21(test_br21_target)
+ .skip (1 << 21)
+test_br21_target:
+ .size test_br21, .-test_br21
+
+
.globl named_data
.p2align 4
.type named_data, at object
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