[clang] [llvm] [IR] Avoid creating icmp/fcmp constant expressions (PR #92885)

[Nicolai Hähnle via llvm-commits]

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@@ -84,28 +84,30 @@ long double ld = -1.0L;
 // CHECK-LE-LABEL: define dso_local void @_Z12test_signbitv(
 // CHECK-LE-SAME: ) #[[ATTR0:[0-9]+]] {
 // CHECK-LE-NEXT:  entry:
-// CHECK-LE-NEXT:    [[FROMBOOL:%.*]] = zext i1 icmp slt (i64 trunc (i128 bitcast (ppc_fp128 0xM3FF00000000000000000000000000000 to i128) to i64), i64 0) to i8
+// CHECK-LE-NEXT:    [[TMP0:%.*]] = icmp slt i64 trunc (i128 bitcast (ppc_fp128 0xM3FF00000000000000000000000000000 to i128) to i64), 0
+// CHECK-LE-NEXT:    [[FROMBOOL:%.*]] = zext i1 [[TMP0]] to i8
 // CHECK-LE-NEXT:    store i8 [[FROMBOOL]], ptr @b, align 1
-// CHECK-LE-NEXT:    [[TMP0:%.*]] = load ppc_fp128, ptr @ld, align 16
-// CHECK-LE-NEXT:    [[TMP1:%.*]] = bitcast ppc_fp128 [[TMP0]] to i128
-// CHECK-LE-NEXT:    [[TMP2:%.*]] = trunc i128 [[TMP1]] to i64
-// CHECK-LE-NEXT:    [[TMP3:%.*]] = icmp slt i64 [[TMP2]], 0
-// CHECK-LE-NEXT:    [[FROMBOOL1:%.*]] = zext i1 [[TMP3]] to i8
+// CHECK-LE-NEXT:    [[TMP1:%.*]] = load ppc_fp128, ptr @ld, align 16
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nhaehnle wrote:

That diff is awful. We should make `update_cc_test_checks.py` use `collect_original_check_lines` :)

https://github.com/llvm/llvm-project/pull/92885