[llvm] ec27c5f - [RISCV] Prefer to lower MC_GlobalAddress operands to .Lfoo$local
Fangrui Song via llvm-commits
llvm-commits at lists.llvm.org
Tue May 11 11:29:50 PDT 2021
Author: Fangrui Song
Date: 2021-05-11T11:29:45-07:00
New Revision: ec27c5f170441ab54295830aa9f7d376406c6a0f
URL: https://github.com/llvm/llvm-project/commit/ec27c5f170441ab54295830aa9f7d376406c6a0f
DIFF: https://github.com/llvm/llvm-project/commit/ec27c5f170441ab54295830aa9f7d376406c6a0f.diff
LOG: [RISCV] Prefer to lower MC_GlobalAddress operands to .Lfoo$local
Similar to X86 D73230 and AArch64 D101872
With this change, we can set dso_local in clang's -fpic -fno-semantic-interposition mode,
for default visibility external linkage non-ifunc-non-COMDAT definitions.
For such dso_local definitions, variable access/taking the address of a
function/calling a function will go through a local alias to avoid GOT/PLT.
Reviewed By: jrtc27, luismarques
Differential Revision: https://reviews.llvm.org/D101875
Added:
llvm/test/CodeGen/RISCV/elf-preemption.ll
Modified:
llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
Removed:
################################################################################
diff --git a/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp b/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
index 1841e8a0a432..a5c847fd2491 100644
--- a/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
+++ b/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp
@@ -109,7 +109,7 @@ bool llvm::LowerRISCVMachineOperandToMCOperand(const MachineOperand &MO,
MCOp = lowerSymbolOperand(MO, MO.getMBB()->getSymbol(), AP);
break;
case MachineOperand::MO_GlobalAddress:
- MCOp = lowerSymbolOperand(MO, AP.getSymbol(MO.getGlobal()), AP);
+ MCOp = lowerSymbolOperand(MO, AP.getSymbolPreferLocal(*MO.getGlobal()), AP);
break;
case MachineOperand::MO_BlockAddress:
MCOp = lowerSymbolOperand(
diff --git a/llvm/test/CodeGen/RISCV/elf-preemption.ll b/llvm/test/CodeGen/RISCV/elf-preemption.ll
new file mode 100644
index 000000000000..11f8736d1d14
--- /dev/null
+++ b/llvm/test/CodeGen/RISCV/elf-preemption.ll
@@ -0,0 +1,288 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=riscv32 -relocation-model=static < %s \
+; RUN: | FileCheck %s --check-prefix=RV32-STATIC
+; RUN: llc -mtriple=riscv32 -relocation-model=pic < %s \
+; RUN: | FileCheck %s --check-prefix=RV32-PIC
+; RUN: llc -mtriple=riscv64 -relocation-model=static < %s \
+; RUN: | FileCheck %s --check-prefix=RV64-STATIC
+; RUN: llc -mtriple=riscv64 -relocation-model=pic < %s \
+; RUN: | FileCheck %s --check-prefix=RV64-PIC
+
+ at preemptable_var = dso_preemptable global i32 42
+define i32* @get_preemptable_var() nounwind {
+; RV32-STATIC-LABEL: get_preemptable_var:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(preemptable_var)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(preemptable_var)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: get_preemptable_var:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB0_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %got_pcrel_hi(preemptable_var)
+; RV32-PIC-NEXT: lw a0, %pcrel_lo(.LBB0_1)(a0)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: get_preemptable_var:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(preemptable_var)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(preemptable_var)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: get_preemptable_var:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB0_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %got_pcrel_hi(preemptable_var)
+; RV64-PIC-NEXT: ld a0, %pcrel_lo(.LBB0_1)(a0)
+; RV64-PIC-NEXT: ret
+ ret i32* @preemptable_var
+}
+
+ at dsolocal_var = dso_local global i32 42
+define i32* @get_dsolocal_var() nounwind {
+; RV32-STATIC-LABEL: get_dsolocal_var:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(dsolocal_var)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(dsolocal_var)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: get_dsolocal_var:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB1_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %pcrel_hi(.Ldsolocal_var$local)
+; RV32-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB1_1)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: get_dsolocal_var:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(dsolocal_var)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(dsolocal_var)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: get_dsolocal_var:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB1_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %pcrel_hi(.Ldsolocal_var$local)
+; RV64-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB1_1)
+; RV64-PIC-NEXT: ret
+ ret i32* @dsolocal_var
+}
+
+ at weak_dsolocal_var = weak dso_local global i32 42
+define i32* @get_weak_dsolocal_var() nounwind {
+; RV32-STATIC-LABEL: get_weak_dsolocal_var:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(weak_dsolocal_var)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(weak_dsolocal_var)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: get_weak_dsolocal_var:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB2_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %pcrel_hi(weak_dsolocal_var)
+; RV32-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB2_1)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: get_weak_dsolocal_var:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(weak_dsolocal_var)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(weak_dsolocal_var)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: get_weak_dsolocal_var:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB2_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %pcrel_hi(weak_dsolocal_var)
+; RV64-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB2_1)
+; RV64-PIC-NEXT: ret
+ ret i32* @weak_dsolocal_var
+}
+
+ at hidden_var = hidden global i32 42
+define i32* @get_hidden_var() nounwind {
+; RV32-STATIC-LABEL: get_hidden_var:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(hidden_var)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(hidden_var)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: get_hidden_var:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB3_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %pcrel_hi(hidden_var)
+; RV32-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB3_1)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: get_hidden_var:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(hidden_var)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(hidden_var)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: get_hidden_var:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB3_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %pcrel_hi(hidden_var)
+; RV64-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB3_1)
+; RV64-PIC-NEXT: ret
+ ret i32* @hidden_var
+}
+
+ at protected_var = protected global i32 42
+define i32* @get_protected_var() nounwind {
+; RV32-STATIC-LABEL: get_protected_var:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(protected_var)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(protected_var)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: get_protected_var:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB4_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %pcrel_hi(protected_var)
+; RV32-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB4_1)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: get_protected_var:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(protected_var)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(protected_var)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: get_protected_var:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB4_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %pcrel_hi(protected_var)
+; RV64-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB4_1)
+; RV64-PIC-NEXT: ret
+ ret i32* @protected_var
+}
+
+define dso_preemptable void()* @preemptable_func() nounwind {
+; RV32-STATIC-LABEL: preemptable_func:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(preemptable_func)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(preemptable_func)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: preemptable_func:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB5_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %got_pcrel_hi(preemptable_func)
+; RV32-PIC-NEXT: lw a0, %pcrel_lo(.LBB5_1)(a0)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: preemptable_func:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(preemptable_func)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(preemptable_func)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: preemptable_func:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB5_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %got_pcrel_hi(preemptable_func)
+; RV64-PIC-NEXT: ld a0, %pcrel_lo(.LBB5_1)(a0)
+; RV64-PIC-NEXT: ret
+ ret void()* bitcast(void()*()* @preemptable_func to void()*)
+}
+
+define dso_local void()* @dsolocal_func() nounwind {
+; RV32-STATIC-LABEL: dsolocal_func:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(dsolocal_func)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(dsolocal_func)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: dsolocal_func:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB6_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %pcrel_hi(.Ldsolocal_func$local)
+; RV32-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB6_1)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: dsolocal_func:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(dsolocal_func)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(dsolocal_func)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: dsolocal_func:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB6_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %pcrel_hi(.Ldsolocal_func$local)
+; RV64-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB6_1)
+; RV64-PIC-NEXT: ret
+ ret void()* bitcast(void()*()* @dsolocal_func to void()*)
+}
+
+define weak dso_local void()* @weak_dsolocal_func() nounwind {
+; RV32-STATIC-LABEL: weak_dsolocal_func:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: lui a0, %hi(weak_dsolocal_func)
+; RV32-STATIC-NEXT: addi a0, a0, %lo(weak_dsolocal_func)
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: weak_dsolocal_func:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: .LBB7_1: # Label of block must be emitted
+; RV32-PIC-NEXT: auipc a0, %pcrel_hi(weak_dsolocal_func)
+; RV32-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB7_1)
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: weak_dsolocal_func:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: lui a0, %hi(weak_dsolocal_func)
+; RV64-STATIC-NEXT: addi a0, a0, %lo(weak_dsolocal_func)
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: weak_dsolocal_func:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: .LBB7_1: # Label of block must be emitted
+; RV64-PIC-NEXT: auipc a0, %pcrel_hi(weak_dsolocal_func)
+; RV64-PIC-NEXT: addi a0, a0, %pcrel_lo(.LBB7_1)
+; RV64-PIC-NEXT: ret
+ ret void()* bitcast(void()*()* @weak_dsolocal_func to void()*)
+}
+
+;; call .Ldsolocal_func$local either resolves to a constant at assembly time
+;; or produces a relocation referencing a non-preemptible local symbol.
+define dso_local void @call_dsolocal_func() nounwind {
+; RV32-STATIC-LABEL: call_dsolocal_func:
+; RV32-STATIC: # %bb.0:
+; RV32-STATIC-NEXT: addi sp, sp, -16
+; RV32-STATIC-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
+; RV32-STATIC-NEXT: call dsolocal_func
+; RV32-STATIC-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
+; RV32-STATIC-NEXT: addi sp, sp, 16
+; RV32-STATIC-NEXT: ret
+;
+; RV32-PIC-LABEL: call_dsolocal_func:
+; RV32-PIC: # %bb.0:
+; RV32-PIC-NEXT: addi sp, sp, -16
+; RV32-PIC-NEXT: sw ra, 12(sp) # 4-byte Folded Spill
+; RV32-PIC-NEXT: call .Ldsolocal_func$local
+; RV32-PIC-NEXT: lw ra, 12(sp) # 4-byte Folded Reload
+; RV32-PIC-NEXT: addi sp, sp, 16
+; RV32-PIC-NEXT: ret
+;
+; RV64-STATIC-LABEL: call_dsolocal_func:
+; RV64-STATIC: # %bb.0:
+; RV64-STATIC-NEXT: addi sp, sp, -16
+; RV64-STATIC-NEXT: sd ra, 8(sp) # 8-byte Folded Spill
+; RV64-STATIC-NEXT: call dsolocal_func
+; RV64-STATIC-NEXT: ld ra, 8(sp) # 8-byte Folded Reload
+; RV64-STATIC-NEXT: addi sp, sp, 16
+; RV64-STATIC-NEXT: ret
+;
+; RV64-PIC-LABEL: call_dsolocal_func:
+; RV64-PIC: # %bb.0:
+; RV64-PIC-NEXT: addi sp, sp, -16
+; RV64-PIC-NEXT: sd ra, 8(sp) # 8-byte Folded Spill
+; RV64-PIC-NEXT: call .Ldsolocal_func$local
+; RV64-PIC-NEXT: ld ra, 8(sp) # 8-byte Folded Reload
+; RV64-PIC-NEXT: addi sp, sp, 16
+; RV64-PIC-NEXT: ret
+ call void()* @dsolocal_func()
+ ret void
+}
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