[llvm] [CodeGen] Allow mixed scalar type constraints for inline asm (PR #65465)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,72 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
+
+; C source used for generating this test:
+
+; unsigned test(float f)
+; {
+;    unsigned i;
+;    asm volatile ("" : "=r" (i) : "0" (f));
+;    return i;
+; }
+
+
+define i32 @test_int_float(float %f) {
+; CHECK-LABEL: test_int_float:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movss %xmm0, -{{[0-9]+}}(%rsp)
+; CHECK-NEXT:    movl -{{[0-9]+}}(%rsp), %eax
+; CHECK-NEXT:    #APP
+; CHECK-NEXT:    #NO_APP
+; CHECK-NEXT:    movl %eax, -{{[0-9]+}}(%rsp)
+; CHECK-NEXT:    retq
+entry:
+  %f.addr = alloca float, align 4
+  %i = alloca i32, align 4
+  store float %f, ptr %f.addr, align 4
+  %load_f = load float, ptr %f.addr, align 4
+  %asm_call = call i32 asm sideeffect "", "=r,0,~{dirflag},~{fpsr},~{flags}"(float %load_f)
+  store i32 %asm_call, ptr %i, align 4
+  %load_i = load i32, ptr %i, align 4
+  ret i32 %load_i
+}
+
+define i32 @test_int_ptr(float* %f) {
+; CHECK-LABEL: test_int_ptr:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movq %rdi, %rax
+; CHECK-NEXT:    movq %rdi, -{{[0-9]+}}(%rsp)
+; CHECK-NEXT:    #APP
+; CHECK-NEXT:    #NO_APP
+; CHECK-NEXT:    movl %eax, -{{[0-9]+}}(%rsp)
+; CHECK-NEXT:    # kill: def $eax killed $eax killed $rax
+; CHECK-NEXT:    retq
+entry:
+  %f.addr = alloca float*, align 4
+  %i = alloca i32, align 4
+  store float* %f, ptr %f.addr, align 4
+  %load_f = load float*, ptr %f.addr, align 4
----------------
arsenm wrote:

Test needs to be updated to use opaque pointers. Also you don't need all of this intermediate alloca stuff, you can simplify the incoming values and uses 

https://github.com/llvm/llvm-project/pull/65465