[clang] Fix codegen of consteval functions returning an empty class, and related issues (PR #93115)

[Eli Friedman via cfe-commits]

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@@ -44,20 +44,20 @@ struct S1 f1(struct S1 s1) { return s1; }
 
 // CHECK-SOFT: define{{.*}} void @_Z2f22S2(ptr dead_on_unwind noalias nocapture writable writeonly sret(%struct.S2) align 8 %agg.result, [4 x i32] %s2.coerce)
 // CHECK-HARD: define{{.*}} arm_aapcs_vfpcc [2 x <2 x i32>] @_Z2f22S2([2 x <2 x i32>] returned %s2.coerce)
-// CHECK-FULL: define{{.*}} arm_aapcs_vfpcc %struct.S2 @_Z2f22S2(%struct.S2 returned %s2.coerce)
+// CHECK-FULL: define{{.*}} arm_aapcs_vfpcc %struct.S2 @_Z2f22S2(%struct.S2 %s2.coerce)
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efriedma-quic wrote:

This is also the instcombine issue.

https://github.com/llvm/llvm-project/pull/93115