[llvm] [LegalizeTypes][MSP430] Soften FAKE_USE operand (PR #142714)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,31 @@
+; RUN: llc -stop-after=finalize-isel -filetype=asm -o - < %s | FileCheck %s
+target datalayout = "e-m:e-p:16:16-i32:16-i64:16-f32:16-f64:16-a:8-n8:16-S16"
+target triple = "msp430"
+
+; CHECK:       bb.0.entry:
+; CHECK:       %0:gr16 = MOV16ri
+; CHECK-DAG:   FAKE_USE killed %0
+; CHECK:       %1:gr16 = MOV16ri
+; CHECK-DAG:   FAKE_USE killed %1
+; CHECK:       %2:gr16 = MOV16ri
+; CHECK-DAG:   FAKE_USE killed %2
+; CHECK:       %3:gr16 = MOV16ri
+; CHECK-DAG:   FAKE_USE killed %3
+; CHECK:       RET
+define void @test-double() {
+entry:
+  call void (...) @llvm.fake.use(double -8.765430e+02)
+  ret void
+}
+
+; CHECK:       bb.0.entry:
+; CHECK:       %0:gr16 = MOV16ri
+; CHECK-DAG:   FAKE_USE killed %0
+; CHECK:       %1:gr16 = MOV16ri
+; CHECK-DAG:   FAKE_USE killed %1
+; CHECK:       RET
+define void @test-float() {
+entry:
+  call void (...) @llvm.fake.use(float -8.76e+02)
+  ret void
+}
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arsenm wrote:

Can you test with some non-constant inputs 

https://github.com/llvm/llvm-project/pull/142714