[clang] Fix complex long double division with -mno-x87. (PR #133152)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,49 @@
+// RUN %clang_cc1 %s -O0 -emit-llvm -triple x86_64-unknown-unknown \
+// RUN -verify -complex-range=promoted -o - | FileCheck %s
+
+// RUN %clang_cc1 %s -O0 -emit-llvm -triple x86_64-unknown-unknown \
+// RUN -verify=nopromotion -complex-range=promoted -target-feature -x87 -o - | FileCheck %s --check-prefix=NOX87
+
+// RUN: %clang_cc1 %s -O0 -emit-llvm -triple x86_64-unknown-windows \
+// RUN: -verify=nopromotion -complex-range=promoted -o - | FileCheck %s --check-prefix=NOX87
+
+// RUN: %clang_cc1 %s -O0 -emit-llvm -triple x86_64-unknown-windows \
+// RUN: -verify=nopromotion -complex-range=promoted -target-feature -x87 -o - | FileCheck %s --check-prefix=NOX87
+
+
+
+// expected-no-diagnostics
+
+// CHECK-LABEL: define dso_local <2 x float> @divd
+_Complex float divd(_Complex float a, _Complex float b) {
+  // CHECK: fpext float {{.*}} to double
+  // CHECK: fpext float {{.*}} to double
+  // CHECK: fdiv double
+  // CHECK: fdiv double
+  // CHECK: fptrunc double {{.*}} to float
+  // CHECK: fptrunc double {{.*}} to float
+
+  // NOX87: fpext float {{.*}} to double
+  // NOX87: fpext float {{.*}} to double
+  // NOX87: fdiv double
+  // NOX87: fdiv double
+  // NOX87: fptrunc double {{.*}} to float
+  // NOX87: fptrunc double {{.*}} to float
+
+  return a / b;
+}
+
+// CHECK-LABEL: define dso_local { double, double } @divf
+_Complex double divf(_Complex double a, _Complex double b) {
+  // CHECK: fpext double {{.*}} to x86_fp80
+  // CHECK: fpext double {{.*}} to x86_fp80
+  // CHECK: fdiv x86_fp80
+  // CHECK: fdiv x86_fp80
+  // CHECK: fptrunc x86_fp80
+  // CHECK: fptrunc x86_fp80
+
+  // NOX87: fdiv double
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andykaylor wrote:

We fall back on "improved" in this case, right? Can you add more checks to show that?

https://github.com/llvm/llvm-project/pull/133152