6 Commits

Author	SHA1	Message	Date
Benjamin Kramer	f50125ecaa	DAGCombine add (sext i1), X into sub X, (zext i1) if sext from i1 is illegal. The latter usually compiles into smaller code. ... example code: unsigned foo(unsigned x, unsigned y) { if (x != 0) y--; return y; } before: _foo: ## @foo cmpl $1, 4(%esp) ## encoding: [0x83,0x7c,0x24,0x04,0x01] sbbl %eax, %eax ## encoding: [0x19,0xc0] notl %eax ## encoding: [0xf7,0xd0] addl 8(%esp), %eax ## encoding: [0x03,0x44,0x24,0x08] ret ## encoding: [0xc3] after: _foo: ## @foo cmpl $1, 4(%esp) ## encoding: [0x83,0x7c,0x24,0x04,0x01] movl 8(%esp), %eax ## encoding: [0x8b,0x44,0x24,0x08] adcl $-1, %eax ## encoding: [0x83,0xd0,0xff] ret ## encoding: [0xc3] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122455 91177308-0d34-0410-b5e6-96231b3b80d8	2010-12-22 23:17:45 +00:00
Chris Lattner	23a0199f05	now that addc/adde are gone, "ADDC" in the X86 backend uses EFLAGS results, ... the same as setcc. Optimize ADDC(0,0,FLAGS) -> SET_CARRY(FLAGS). This is a step towards finishing off PR5443. In the testcase in that bug we now get: movq %rdi, %rax addq %rsi, %rax sbbq %rcx, %rcx testb $1, %cl setne %dl ret instead of: movq %rdi, %rax addq %rsi, %rax movl $0, %ecx adcq $0, %rcx testq %rcx, %rcx setne %dl ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122219 91177308-0d34-0410-b5e6-96231b3b80d8	2010-12-20 01:37:09 +00:00
Chris Lattner	39ffcb7b62	We lower setb to sbb with the hope that the and will go away, when it ... doesn't, match it back to setb. On a 64-bit version of the testcase before we'd get: movq %rdi, %rax addq %rsi, %rax sbbb %dl, %dl andb $1, %dl ret now we get: movq %rdi, %rax addq %rsi, %rax setb %dl ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122217 91177308-0d34-0410-b5e6-96231b3b80d8	2010-12-20 01:16:03 +00:00
Chris Lattner	b00cd1c899	merge a target-specific add test into x86 directory. ... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95654 91177308-0d34-0410-b5e6-96231b3b80d8	2010-02-09 06:35:50 +00:00
Chris Lattner	7816239985	merge another test in, drop the trivially constant folded cases. ... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95653 91177308-0d34-0410-b5e6-96231b3b80d8	2010-02-09 06:33:27 +00:00
Chris Lattner	71d845c48a	consolidate and filecheckize two tests. ... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95652 91177308-0d34-0410-b5e6-96231b3b80d8	2010-02-09 06:24:00 +00:00