llvm-project/llvm/lib/Target/RISCV
Sameer AbuAsal e01e711c64 [RISCV] Tail calls don't need to save return address
Summary:
 When expanding the PseudoTail in expandFunctionCall() we were using X6
 to save the return address. Since this is a tail call the return
 address is not needed, this patch replaces it with X0 to be ignored.

 This matches the behaviour listed in the ISA V2.2 document page 110.
 tail offset -----> jalr x0, x6, offset

 GCC exhibits the same behavior.

Reviewers: apazos, asb, mgrang

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01

Differential Revision: https://reviews.llvm.org/D48343

llvm-svn: 335239
2018-06-21 14:37:09 +00:00
..
AsmParser [RISCV] AsmParser support for the li pseudo instruction 2018-06-07 15:35:47 +00:00
Disassembler Rename DEBUG macro to LLVM_DEBUG. 2018-05-14 12:53:11 +00:00
InstPrinter [RISCV] Tablegen-driven Instruction Compression. 2018-04-06 21:07:05 +00:00
MCTargetDesc [RISCV] Tail calls don't need to save return address 2018-06-21 14:37:09 +00:00
TargetInfo Fix RISCV build after r318352 2017-11-16 18:39:31 +00:00
CMakeLists.txt [RISCV] Tablegen-driven Instruction Compression. 2018-04-06 21:07:05 +00:00
LLVMBuild.txt [RISCV] Initial codegen support for ALU operations 2017-10-19 21:37:38 +00:00
RISCV.h [RISCV] Codegen support for memory operations on global addresses 2017-11-08 13:24:21 +00:00
RISCV.td [RISCV] Define FeatureRelax and shouldForceRelocation for RISCV linker relaxation 2018-05-15 01:28:50 +00:00
RISCVAsmPrinter.cpp Revert "[RISCV] implement li pseudo instruction" 2018-04-18 19:02:31 +00:00
RISCVCallingConv.td [RISCV] Add custom CC_RISCV calling convention and improved call support 2017-12-11 12:49:02 +00:00
RISCVFrameLowering.cpp [RISCV] Preserve stack space for outgoing arguments when the function contain variable size objects 2018-03-20 01:39:17 +00:00
RISCVFrameLowering.h [RISCV] Preserve stack space for outgoing arguments when the function contain variable size objects 2018-03-20 01:39:17 +00:00
RISCVISelDAGToDAG.cpp [RISCV] Add peepholes for Global Address lowering patterns 2018-05-29 19:34:54 +00:00
RISCVISelLowering.cpp [RISCV] Add codegen support for atomic load/stores with RV32A 2018-06-13 12:04:51 +00:00
RISCVISelLowering.h [RISCV] Add codegen support for atomic load/stores with RV32A 2018-06-13 12:04:51 +00:00
RISCVInstrFormats.td [RISCV] AsmParser support for the li pseudo instruction 2018-06-07 15:35:47 +00:00
RISCVInstrFormatsC.td [RISCV] MC layer support for the remaining RVC instructions 2017-12-13 09:32:55 +00:00
RISCVInstrInfo.cpp [RISCV] Lower the tail pseudoinstruction 2018-05-23 22:44:08 +00:00
RISCVInstrInfo.h [RISCV] Implement isLoadFromStackSlot and isStoreToStackSlot 2018-04-26 15:34:27 +00:00
RISCVInstrInfo.td [RISCV] Add InstAlias definitions for sgt and sgtu 2018-06-20 12:54:02 +00:00
RISCVInstrInfoA.td [RISCV] Add codegen support for atomic load/stores with RV32A 2018-06-13 12:04:51 +00:00
RISCVInstrInfoC.td [RISCV] Add c.mv rs1, rs2 pattern for addi rs1, rs2, 0 2018-04-12 19:22:40 +00:00
RISCVInstrInfoD.td [RISCV] Add InstAlias definitions for fgt.{s|d}, fge.{s|d} 2018-06-20 14:03:02 +00:00
RISCVInstrInfoF.td [RISCV] Accept fmv.s.x and fmv.x.s as mnemonic aliases for fmv.w.x and fmv.x.w 2018-06-20 18:42:25 +00:00
RISCVInstrInfoM.td [RISCV] Codegen support for the standard RV32M instruction set extension 2018-01-18 12:36:38 +00:00
RISCVMCInstLower.cpp [RISCV] Add codegen for RV32F floating point load/store 2018-03-20 13:26:12 +00:00
RISCVMachineFunctionInfo.h [RISCV] Codegen support for RV32D floating point load/store, fadd.d, calling conv 2018-04-12 05:34:25 +00:00
RISCVRegisterInfo.cpp [RISCV] Set isReMaterializable on ADDI and LUI instructions 2018-05-17 15:51:37 +00:00
RISCVRegisterInfo.h [RISCV] Set isReMaterializable on ADDI and LUI instructions 2018-05-17 15:51:37 +00:00
RISCVRegisterInfo.td [RISCV] Lower the tail pseudoinstruction 2018-05-23 22:44:08 +00:00
RISCVSubtarget.cpp [RISCV] Initial codegen support for ALU operations 2017-10-19 21:37:38 +00:00
RISCVSubtarget.h [RISCV] Define FeatureRelax and shouldForceRelocation for RISCV linker relaxation 2018-05-15 01:28:50 +00:00
RISCVTargetMachine.cpp [RISCV] Codegen support for atomic operations on RV32I 2018-06-13 11:58:46 +00:00
RISCVTargetMachine.h [RISCV] Initial codegen support for ALU operations 2017-10-19 21:37:38 +00:00
RISCVTargetObjectFile.cpp [RISCV] Use init_array instead of ctors for RISCV target, by default 2018-03-24 18:37:19 +00:00
RISCVTargetObjectFile.h [RISCV] Use init_array instead of ctors for RISCV target, by default 2018-03-24 18:37:19 +00:00