[llvm] [RISCV] Add combine for shadd family of instructions. (PR #130829)

[Min-Yih Hsu via llvm-commits]

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@@ -0,0 +1,113 @@
+; RUN: llc -mtriple=riscv32-pc-unknown-gnu -mattr=+zba %s -o - | FileCheck %s
+
+declare dso_local i32 @callee1(i32 noundef) local_unnamed_addr
+declare dso_local i32 @callee2(i32 noundef, i32 noundef) local_unnamed_addr
+declare dso_local i32 @callee(i32 noundef, i32 noundef, i32 noundef, i32 noundef) local_unnamed_addr
+
+; CHECK-LABEL: t1:
+; CHECK: sh2add
+; CHECK: sh2add
+; CHECK: sh2add
+; CHECK: tail callee
+
+define dso_local void @t1(i32 noundef %a, i32 noundef %b, i32 noundef %c, i32 noundef %d) local_unnamed_addr #0 {
+entry:
+  %shl = shl i32 %a, 2
+  %add = add nsw i32 %shl, 45
+  %add1 = add nsw i32 %add, %b
+  %add3 = add nsw i32 %add, %c
+  %add5 = add nsw i32 %shl, %d
+  %call = tail call i32 @callee(i32 noundef %add1, i32 noundef %add1, i32 noundef %add3, i32 noundef %add5)
+  ret void
+}
+
+; CHECK-LABEL: t2:
+; CHECK: slli
+; CHECK-NOT: sh2add
+; CHECK: tail callee 
+
+define dso_local void @t2(i32 noundef %a, i32 noundef %b, i32 noundef %c) local_unnamed_addr #0 {
+entry:
+  %shl = shl i32 %a, 2
+  %add = add nsw i32 %shl, 42
+  %add4 = add nsw i32 %add, %b
+  %add7 = add nsw i32 %add, %c
+  %call = tail call i32 @callee(i32 noundef %shl, i32 noundef %add, i32 noundef %add4, i32 noundef %add7)
+  ret void
+}
+
+; CHECK-LABEL: t3
+; CHECK slli
+; CHECK-NOT: sh2add
+; CHECK: tail callee 
+
+define dso_local void @t3(i32 noundef %a, i32 noundef %b, i32 noundef %c, i32 noundef %d, i32 noundef %e) local_unnamed_addr #0 {
+entry:
+  %shl = shl i32 %a, 2
+  %add = add nsw i32 %shl, 42
+  %add1 = add nsw i32 %add, %b
+  %add2 = add nsw i32 %add, %c
+  %add3 = add nsw i32 %add, %d
+  %add4 = add nsw i32 %add, %e
+  %call = tail call i32 @callee(i32 noundef %add1, i32 noundef %add2, i32 noundef %add3, i32 noundef %add4)
+  ret void
+}
+
+; CHECK-LABEL: t4
+; CHECK: sh2add
+; CHECK-NEXT: addi
+; CHECK-NEXT: tail callee1
+
+define dso_local void @t4(i32 noundef %a, i32 noundef %b) local_unnamed_addr #0 {
+entry:
+  %shl = shl i32 %a, 2
+  %add = add nsw i32 %shl, 42
+  %add1 = add nsw i32 %add, %b
+  %call = tail call i32 @callee1(i32 noundef %add1)
+  ret void
+}
+
+; CHECK-LABEL: t5
+; CHECK: sh2add
+; CHECK: sh2add
+; CHECK: tail callee2
+
+define dso_local void @t5(i32 noundef %a, i32 noundef %b, i32 noundef %c) local_unnamed_addr #0 {
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mshockwave wrote:

dso_local and local_unnamed_addr can both be gone I believe.

https://github.com/llvm/llvm-project/pull/130829