| ; This tests against a lowering error in a multiply instruction that produces |
| ; results in a low and high register. This is usually lowered as a mul |
| ; instruction whose dest contains the low portion, and a FakeDef of the high |
| ; portion. The problem is that if the high portion is unused (e.g. the multiply |
| ; is followed by a truncation), the FakeDef may be eliminated, and the register |
| ; allocator may assign the high register to a variable that is live across the |
| ; mul instruction. This is incorrect because the mul instruction smashes the |
| ; register. |
| |
| ; REQUIRES: allow_dump |
| |
| ; RUN: %p2i --target x8632 -i %s --filetype=asm --args -O2 -asm-verbose \ |
| ; RUN: --reg-use=eax,edx -reg-reserve | FileCheck --check-prefix=X8632 %s |
| ; RUN: %p2i --target arm32 -i %s --filetype=asm --args -O2 -asm-verbose \ |
| ; RUN: | FileCheck --check-prefix=ARM32 %s |
| |
| define internal i32 @mul(i64 %a, i64 %b, i32 %c) { |
| ; Force an early use of %c. |
| store i32 %c, i32* undef, align 1 |
| %m = mul i64 %a, %b |
| %t = trunc i64 %m to i32 |
| ; Make many uses of %c to give it high weight. |
| %t1 = add i32 %t, %c |
| %t2 = add i32 %t1, %c |
| %t3 = add i32 %t2, %c |
| ret i32 %t3 |
| } |
| |
| ; For x8632, we want asm-verbose to print the stack offset assignment for lv$c |
| ; ("local variable 'c'") in the prolog, and then have at least one use of lv$c |
| ; in the body, i.e. don't register-allocate edx to %c. |
| |
| ; X8632-LABEL: mul |
| ; X8632: lv$c = |
| ; X8632: lv$c |
| |
| ; For arm32, the failure would manifest as a translation error - no register |
| ; being allocated to the high operand, so we just check for successful |
| ; translation. |
| |
| ; ARM32-LABEL: mul |