Follow the implementation approach suggested by PR6687,
which generates more efficient and more obviously conformant
code. We now test for overflow of the multiply then force
the result to -1 if so. On X86, this generates nice code
like this:
__Z4testl: ## @_Z4testl
## BB#0: ## %entry
subl $12, %esp
movl $4, %eax
mull 16(%esp)
testl %edx, %edx
movl $-1, %ecx
cmovel %eax, %ecx
movl %ecx, (%esp)
call __Znam
addl $12, %esp
ret
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@108927 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed