[llvm] [GISel][RISCV] Add legalizer & selector support for G_FREEZE. (PR #92744)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,164 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=riscv32 -mattr=+f,+v -global-isel -global-isel-abort=1 -verify-machineinstrs < %s 2>&1 | FileCheck %s --check-prefixes=CHECK,RV32
+; RUN: llc -mtriple=riscv64 -mattr=+f,+v -global-isel -global-isel-abort=1 -verify-machineinstrs < %s 2>&1 | FileCheck %s --check-prefixes=CHECK,RV64
+
+%struct.T = type { i32, i32 }
+
+define i32 @freeze_int() {
+; RV32-LABEL: freeze_int:
+; RV32:       # %bb.0:
+; RV32-NEXT:    addi sp, sp, -16
+; RV32-NEXT:    .cfi_def_cfa_offset 16
+; RV32-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
+; RV32-NEXT:    .cfi_offset ra, -4
+; RV32-NEXT:    call __mulsi3
+; RV32-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
+; RV32-NEXT:    addi sp, sp, 16
+; RV32-NEXT:    ret
+;
+; RV64-LABEL: freeze_int:
+; RV64:       # %bb.0:
+; RV64-NEXT:    addi sp, sp, -16
+; RV64-NEXT:    .cfi_def_cfa_offset 16
+; RV64-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
+; RV64-NEXT:    .cfi_offset ra, -8
+; RV64-NEXT:    call __muldi3
+; RV64-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
+; RV64-NEXT:    addi sp, sp, 16
+; RV64-NEXT:    ret
+  %y1 = freeze i32 undef
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arsenm wrote:

Avoid undef here, and non-constant inputs are generally more useful tests 

https://github.com/llvm/llvm-project/pull/92744