1; RUN: not llc -o /dev/null %s -mtriple=i386-unknown-unknown 2>&1 | FileCheck %s 2 3; This test was derived from this C code. The frontend sees that the constraint 4; doesn't accept memory, but the argument is a strict. So it tries to bitcast 5; to an integer of the same size. SelectionDAGBuilder doesn't know how to copy 6; between integers and fp80 so it asserts or crashes. 7; 8; gcc accepts the code. But rejects it if the struct is replaced by an int. From 9; the InlineAsm block those two cases look the same in LLVM IR. So if the single 10; elementstruct case is valid, then the frontend needs to emit different IR. 11 12; typedef struct float4 { 13; float f; 14; } float4; 15; 16; int main() { 17; float4 f4; 18; f4.f = 4.0f; 19; __asm ("fadd %%st(0), %%st(0)" : "+t" (f4)); 20; return 0; 21; } 22 23%struct.float4 = type { float } 24 25; CHECK: error: couldn't allocate output register for constraint '{st}' 26define dso_local i32 @foo() { 27entry: 28 %retval = alloca i32, align 4 29 %f4 = alloca %struct.float4, align 4 30 store i32 0, ptr %retval, align 4 31 store float 4.000000e+00, ptr %f4, align 4 32 %0 = load i32, ptr %f4, align 4 33 %1 = call i32 asm "fadd %st(0), %st(0)", "={st},0,~{dirflag},~{fpsr},~{flags}"(i32 %0) 34 store i32 %1, ptr %f4, align 4 35 ret i32 0 36} 37