[llvm] [RISCV][GISel] Add calling convention support for half (PR #94110)

[Craig Topper via llvm-commits]

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@@ -0,0 +1,516 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=riscv32 -global-isel -stop-after=irtranslator < %s \
+; RUN:   | FileCheck -check-prefix=RV32I %s
+; RUN: llc -mtriple=riscv32 -mattr=+f -global-isel -stop-after=irtranslator < %s \
+; RUN:   | FileCheck -check-prefix=RV32IF %s
+; RUN: llc -mtriple=riscv32 -mattr=+zfh -global-isel -stop-after=irtranslator < %s \
+; RUN:   | FileCheck -check-prefix=RV32IZFH %s
+
+define half @callee_half_in_regs(half %x) nounwind {
+  ; RV32I-LABEL: name: callee_half_in_regs
+  ; RV32I: bb.1 (%ir-block.0):
+  ; RV32I-NEXT:   liveins: $x10
+  ; RV32I-NEXT: {{  $}}
+  ; RV32I-NEXT:   [[COPY:%[0-9]+]]:_(s32) = COPY $x10
+  ; RV32I-NEXT:   [[TRUNC:%[0-9]+]]:_(s16) = G_TRUNC [[COPY]](s32)
+  ; RV32I-NEXT:   [[ANYEXT:%[0-9]+]]:_(s32) = G_ANYEXT [[TRUNC]](s16)
+  ; RV32I-NEXT:   $x10 = COPY [[ANYEXT]](s32)
+  ; RV32I-NEXT:   PseudoRET implicit $x10
+  ;
+  ; RV32IF-LABEL: name: callee_half_in_regs
+  ; RV32IF: bb.1 (%ir-block.0):
+  ; RV32IF-NEXT:   liveins: $f10_f
+  ; RV32IF-NEXT: {{  $}}
+  ; RV32IF-NEXT:   [[COPY:%[0-9]+]]:_(s32) = COPY $f10_f
+  ; RV32IF-NEXT:   [[TRUNC:%[0-9]+]]:_(s16) = G_TRUNC [[COPY]](s32)
+  ; RV32IF-NEXT:   [[ANYEXT:%[0-9]+]]:_(s32) = G_ANYEXT [[TRUNC]](s16)
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topperc wrote:

They should be removed by the combiner, but we stopped before the combiner.

https://github.com/llvm/llvm-project/pull/94110