[llvm-branch-commits] [llvm] [clang] [SPARC] Prefer RDPC over CALL to implement GETPCX for 64-bit target (PR #77196)

[Sergei Barannikov via llvm-branch-commits]

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@@ -0,0 +1,18 @@
+; RUN: llc < %s -relocation-model=pic -mtriple=sparc | FileCheck --check-prefix=CALL %s
+; RUN: llc < %s -relocation-model=pic -mtriple=sparcv9 -mcpu=ultrasparc | FileCheck --check-prefix=CALL %s
+; RUN: llc < %s -relocation-model=pic -mtriple=sparcv9 | FileCheck --check-prefix=RDPC %s
+
+;; SPARC32 and SPARC64 for classic UltraSPARCs implement GETPCX
+;; with a fake `call`.
+;; All other SPARC64 targets implement it with `rd %pc, %o7`.
+
+ at value = external global i32
+
+; CALL: call
+; CALL-NOT: rd %pc
+; RDPC: rd %pc
+; RDPC-not: call
+define i32 @test() {
+  %1 = load i32, i32* @value
+  ret i32 %1
+}
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s-barannikov wrote:

The test should show the full expansion (autogenerate the checks?).




https://github.com/llvm/llvm-project/pull/77196