[clang] [clang][CodeGen] Emit atomic IR in place of optimized libcalls. (PR #73176)

[James Y Knight via cfe-commits]

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@@ -23,7 +23,7 @@ typedef __int128_t int128_t;
 // PPC64-QUADWORD-ATOMICS:    [[TMP3:%.*]] = load atomic i128, ptr [[TMP1:%.*]] acquire, align 16
 //
 // PPC64-LABEL: @test_load(
-// PPC64:    call void @__atomic_load(i64 noundef 16, ptr noundef [[TMP3:%.*]], ptr noundef [[TMP4:%.*]], i32 noundef signext 2)
+// PPC64:    [[TMP3:%.*]] = load atomic i128, ptr [[TMP1:%.*]] acquire, align 16
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jyknight wrote:

A lot of these are now redundant with PPC64-QUADWORD-ATOMICS. I'd make the tests use `--check-prefixes=PPC64,PPC64-QUADWORD-ATOMICS` and `--check-prefixes=PPC64,PPC64-NO-QUADWORD-ATOMICS` so you can share the check lines for the cases where it doesn't differ.

https://github.com/llvm/llvm-project/pull/73176