[llvm] [Mips] Support "$sp" named register (PR #136821)

[YunQiang Su via llvm-commits]

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@@ -18,12 +45,29 @@ define i32 @get_sp() {
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    jr $ra
 ; CHECK-NEXT:    move $2, $sp
-  %1 = call i32 @llvm.read_register.i32(metadata !1)
+  %1 = call i32 @llvm.read_register.i32(metadata !4)
+  ret i32 %1
+}
+
+define i32 @get_$sp() {
+; CHECK-LABEL: get_$sp:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    jr $ra
+; CHECK-NEXT:    move $2, $sp
+  %1 = call i32 @llvm.read_register.i32(metadata !5)
   ret i32 %1
 }
 
 !llvm.named.register.$28 = !{!0}
-!llvm.named.register.sp = !{!1}
+!llvm.named.register.gp = !{!1}
+!llvm.named.register.$gp = !{!2}
+!llvm.named.register.$29 = !{!3}
+!llvm.named.register.sp = !{!4}
+!llvm.named.register.$sp = !{!5}
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wzssyqa wrote:

we need tests to cover all of these register names.

https://github.com/llvm/llvm-project/pull/136821