[RISCV] Specify registers used in DWARF exception handling

Defines RISCV registers for getExceptionPointerRegister() and
getExceptionSelectorRegister().

Differential Revision: https://reviews.llvm.org/D63411
Patch by Edward Jones.
Modified by Alex Bradbury to add CHECK lines to exception-pointer-register.ll.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365301 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/RISCV/RISCVISelLowering.cpp b/lib/Target/RISCV/RISCVISelLowering.cpp
index 6e6324ab0f543645ec24b6f33981285f4f51715b..9befd022a17dc34b89f6ab9a54391baa3380f8f1 100644 (file)
--- a/lib/Target/RISCV/RISCVISelLowering.cpp
+++ b/lib/Target/RISCV/RISCVISelLowering.cpp
@@ -2608,3 +2608,13 @@ Value *RISCVTargetLowering::emitMaskedAtomicCmpXchgIntrinsic(
     Result = Builder.CreateTrunc(Result, Builder.getInt32Ty());
   return Result;
 }
+
+unsigned RISCVTargetLowering::getExceptionPointerRegister(
+    const Constant *PersonalityFn) const {
+  return RISCV::X10;
+}
+
+unsigned RISCVTargetLowering::getExceptionSelectorRegister(
+    const Constant *PersonalityFn) const {
+  return RISCV::X11;
+}

diff --git a/lib/Target/RISCV/RISCVISelLowering.h b/lib/Target/RISCV/RISCVISelLowering.h
index db11ec8c208daf80441f8f1112fbca72be139a20..17db03bbb69e31f8452e1cbf3d84e5febcd8e03a 100644 (file)
--- a/lib/Target/RISCV/RISCVISelLowering.h
+++ b/lib/Target/RISCV/RISCVISelLowering.h
@@ -131,6 +131,16 @@ public:
   bool isDesirableToCommuteWithShift(const SDNode *N,
                                      CombineLevel Level) const override;
 
+  /// If a physical register, this returns the register that receives the
+  /// exception address on entry to an EH pad.
+  unsigned
+  getExceptionPointerRegister(const Constant *PersonalityFn) const override;
+
+  /// If a physical register, this returns the register that receives the
+  /// exception typeid on entry to a landing pad.
+  unsigned
+  getExceptionSelectorRegister(const Constant *PersonalityFn) const override;
+
 private:
   void analyzeInputArgs(MachineFunction &MF, CCState &CCInfo,
                         const SmallVectorImpl<ISD::InputArg> &Ins,

diff --git a/test/CodeGen/RISCV/exception-pointer-register.ll b/test/CodeGen/RISCV/exception-pointer-register.ll
new file mode 100644 (file)
index 0000000..b341268
--- /dev/null
+++ b/test/CodeGen/RISCV/exception-pointer-register.ll
@@ -0,0 +1,130 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=riscv32 -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV32I
+; RUN: llc -mtriple=riscv64 -verify-machineinstrs < %s \
+; RUN:   | FileCheck %s -check-prefix=RV64I
+;
+; Before getExceptionPointerRegister() and getExceptionSelectorRegister()
+; lowering hooks were defined this would trigger an assertion during live
+; variable analysis
+
+declare void @foo(i1* %p);
+declare void @bar(i1* %p);
+declare dso_local i32 @__gxx_personality_v0(...)
+
+define void @caller(i1* %p) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
+; RV32I-LABEL: caller:
+; RV32I:       # %bb.0: # %entry
+; RV32I-NEXT:    addi sp, sp, -16
+; RV32I-NEXT:    .cfi_def_cfa_offset 16
+; RV32I-NEXT:    sw ra, 12(sp)
+; RV32I-NEXT:    sw s0, 8(sp)
+; RV32I-NEXT:    sw s1, 4(sp)
+; RV32I-NEXT:    .cfi_offset ra, -4
+; RV32I-NEXT:    .cfi_offset s0, -8
+; RV32I-NEXT:    .cfi_offset s1, -12
+; RV32I-NEXT:    mv s0, a0
+; RV32I-NEXT:    beqz a0, .LBB0_2
+; RV32I-NEXT:  # %bb.1: # %bb2
+; RV32I-NEXT:  .Ltmp0:
+; RV32I-NEXT:    mv a0, s0
+; RV32I-NEXT:    call bar
+; RV32I-NEXT:  .Ltmp1:
+; RV32I-NEXT:    j .LBB0_3
+; RV32I-NEXT:  .LBB0_2: # %bb1
+; RV32I-NEXT:  .Ltmp2:
+; RV32I-NEXT:    mv a0, s0
+; RV32I-NEXT:    call foo
+; RV32I-NEXT:  .Ltmp3:
+; RV32I-NEXT:  .LBB0_3: # %end2
+; RV32I-NEXT:    lw s1, 4(sp)
+; RV32I-NEXT:    lw s0, 8(sp)
+; RV32I-NEXT:    lw ra, 12(sp)
+; RV32I-NEXT:    .cfi_restore ra
+; RV32I-NEXT:    .cfi_restore s0
+; RV32I-NEXT:    .cfi_restore s1
+; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    .cfi_def_cfa_offset 0
+; RV32I-NEXT:    ret
+; RV32I-NEXT:  .LBB0_4: # %lpad
+; RV32I-NEXT:  .Ltmp4:
+; RV32I-NEXT:    mv s1, a0
+; RV32I-NEXT:    mv a0, s0
+; RV32I-NEXT:    call callee
+; RV32I-NEXT:    mv a0, s1
+; RV32I-NEXT:    call _Unwind_Resume
+;
+; RV64I-LABEL: caller:
+; RV64I:       # %bb.0: # %entry
+; RV64I-NEXT:    addi sp, sp, -32
+; RV64I-NEXT:    .cfi_def_cfa_offset 32
+; RV64I-NEXT:    sd ra, 24(sp)
+; RV64I-NEXT:    sd s0, 16(sp)
+; RV64I-NEXT:    sd s1, 8(sp)
+; RV64I-NEXT:    .cfi_offset ra, -8
+; RV64I-NEXT:    .cfi_offset s0, -16
+; RV64I-NEXT:    .cfi_offset s1, -24
+; RV64I-NEXT:    mv s0, a0
+; RV64I-NEXT:    beqz a0, .LBB0_2
+; RV64I-NEXT:  # %bb.1: # %bb2
+; RV64I-NEXT:  .Ltmp0:
+; RV64I-NEXT:    mv a0, s0
+; RV64I-NEXT:    call bar
+; RV64I-NEXT:  .Ltmp1:
+; RV64I-NEXT:    j .LBB0_3
+; RV64I-NEXT:  .LBB0_2: # %bb1
+; RV64I-NEXT:  .Ltmp2:
+; RV64I-NEXT:    mv a0, s0
+; RV64I-NEXT:    call foo
+; RV64I-NEXT:  .Ltmp3:
+; RV64I-NEXT:  .LBB0_3: # %end2
+; RV64I-NEXT:    ld s1, 8(sp)
+; RV64I-NEXT:    ld s0, 16(sp)
+; RV64I-NEXT:    ld ra, 24(sp)
+; RV64I-NEXT:    .cfi_restore ra
+; RV64I-NEXT:    .cfi_restore s0
+; RV64I-NEXT:    .cfi_restore s1
+; RV64I-NEXT:    addi sp, sp, 32
+; RV64I-NEXT:    .cfi_def_cfa_offset 0
+; RV64I-NEXT:    ret
+; RV64I-NEXT:  .LBB0_4: # %lpad
+; RV64I-NEXT:  .Ltmp4:
+; RV64I-NEXT:    mv s1, a0
+; RV64I-NEXT:    mv a0, s0
+; RV64I-NEXT:    call callee
+; RV64I-NEXT:    mv a0, s1
+; RV64I-NEXT:    call _Unwind_Resume
+entry:
+  %0 = icmp eq i1* %p, null
+  br i1 %0, label %bb1, label %bb2
+
+bb1:
+  invoke void @foo(i1* %p) to label %end1 unwind label %lpad
+
+bb2:
+  invoke void @bar(i1* %p) to label %end2 unwind label %lpad
+
+lpad:
+  %1 = landingpad { i8*, i32 } cleanup
+  call void @callee(i1* %p)
+  resume { i8*, i32 } %1
+
+end1:
+  ret void
+
+end2:
+  ret void
+}
+
+define internal void @callee(i1* %p) {
+; RV32I-LABEL: callee:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    .cfi_def_cfa_offset 0
+; RV32I-NEXT:    ret
+;
+; RV64I-LABEL: callee:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    .cfi_def_cfa_offset 0
+; RV64I-NEXT:    ret
+  ret void
+}