[llvm] [Mips] Remove `size` operand of LwRxPcTcp16 / LwRxPcTcpX16 (PR #157348)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-mips

Author: Sergei Barannikov (s-barannikov)

<details>
<summary>Changes</summary>

There is no such operand on LW instructions. It is neither encoded nor printed, and was only inserted by MipsConstantIslands pass but never used after that.

---
Full diff: https://github.com/llvm/llvm-project/pull/157348.diff


2 Files Affected:

- (modified) llvm/lib/Target/Mips/Mips16InstrInfo.td (+3-2) 
- (modified) llvm/lib/Target/Mips/MipsConstantIslandPass.cpp (-1) 


``````````diff
diff --git a/llvm/lib/Target/Mips/Mips16InstrInfo.td b/llvm/lib/Target/Mips/Mips16InstrInfo.td
index fb2a83dc90ea9..d7948267de5d6 100644
--- a/llvm/lib/Target/Mips/Mips16InstrInfo.td
+++ b/llvm/lib/Target/Mips/Mips16InstrInfo.td
@@ -88,7 +88,7 @@ class FRI16_ins<bits<5> op, string asmstr,
 
 class FRI16_TCP_ins<bits<5> _op, string asmstr,
                     InstrItinClass itin>:
-  FRI16<_op, (outs CPU16Regs:$rx), (ins pcrel16:$imm8, i32imm:$size),
+  FRI16<_op, (outs CPU16Regs:$rx), (ins pcrel16:$imm8),
             !strconcat(asmstr, "\t$rx, $imm8\t# 16 bit inst"), [], itin>;
 
 class FRI16R_ins_base<bits<5> op, string asmstr, string asmstr2,
@@ -216,7 +216,7 @@ class FEXT_RI16_B_ins<bits<5> _op, string asmstr,
 
 class FEXT_RI16_TCP_ins<bits<5> _op, string asmstr,
                         InstrItinClass itin>:
-  FEXT_RI16<_op, (outs CPU16Regs:$rx), (ins pcrel16:$imm16, i32imm:$size),
+  FEXT_RI16<_op, (outs CPU16Regs:$rx), (ins pcrel16:$imm16),
             !strconcat(asmstr, "\t$rx, $imm16"), [], itin>;
 
 class FEXT_2RI16_ins<bits<5> _op, string asmstr,
@@ -857,6 +857,7 @@ def LwRxSpImmX16: FEXT_RRI16_mem_ins<0b10010, "lw", mem16sp, II_LW>, MayLoad;
 def LwRxPcTcp16: FRI16_TCP_ins<0b10110, "lw", II_LW>, MayLoad;
 
 def LwRxPcTcpX16: FEXT_RI16_TCP_ins<0b10110, "lw", II_LW>, MayLoad;
+
 //
 // Format: MOVE r32, rz MIPS16e
 // Purpose: Move
diff --git a/llvm/lib/Target/Mips/MipsConstantIslandPass.cpp b/llvm/lib/Target/Mips/MipsConstantIslandPass.cpp
index 8699807b6bf2b..31a229a0fd102 100644
--- a/llvm/lib/Target/Mips/MipsConstantIslandPass.cpp
+++ b/llvm/lib/Target/Mips/MipsConstantIslandPass.cpp
@@ -1647,7 +1647,6 @@ void MipsConstantIslands::prescanForConstants() {
           MI.removeOperand(1);
           MI.removeOperand(1);
           MI.addOperand(MachineOperand::CreateCPI(index, 0));
-          MI.addOperand(MachineOperand::CreateImm(4));
         }
         break;
       }

``````````

</details>


https://github.com/llvm/llvm-project/pull/157348