[GlobalISel] IRTranslator: Translate the intrinsics ignored by CodeGen

[volkan]

Summary

Translate llvm.assume, llvm.var.annotation and llvm.sideeffect to nothing
as they have no effect on CodeGen.

[arsenm]

LGTM

[arsenm]

lib/CodeGen/GlobalISel/IRTranslator.cpp

1109–1110 ↗

(On Diff #203598)

Might as well just merge these cases

[volkan]

Merged the switch cases.

llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp

   }
   case Intrinsic::invariant_end:
     return true;
+  case Intrinsic::assume:
+  case Intrinsic::var_annotation:
+  case Intrinsic::sideeffect:
+    // Discard annotate attributes, assumptions, and artificial side-effects.
+    return true;
   }
   return false;
 }

llvm/test/CodeGen/AArch64/GlobalISel/arm64-irtranslator.ll

   %y = call float @llvm.rint.f32(float %x)
   ret float %y
 }
+
+declare void @llvm.assume(i1)
+define void @test_assume(i1 %x) {
+  ; CHECK-LABEL: name:            test_assume
+  ; CHECK-NOT: llvm.assume
+  ; CHECK: RET_ReallyLR
+  call void @llvm.assume(i1 %x)
+  ret void
+}
+
+declare void @llvm.sideeffect()
+define void @test_sideeffect() {
+  ; CHECK-LABEL: name:            test_sideeffect
+  ; CHECK-NOT: llvm.sideeffect
+  ; CHECK: RET_ReallyLR
+  call void @llvm.sideeffect()
+  ret void
+}
+
+declare void @llvm.var.annotation(i8*, i8*, i8*, i32)
+define void @test_var_annotation(i8*, i8*, i8*, i32) {
+  ; CHECK-LABEL: name:            test_var_annotation
+  ; CHECK-NOT: llvm.var.annotation
+  ; CHECK: RET_ReallyLR
+  call void @llvm.var.annotation(i8* %0, i8* %1, i8* %2, i32 %3)
+  ret void
+}