From f6ddc4a1deddc05e1310c338e46adf4f66eccf6b Mon Sep 17 00:00:00 2001 From: Benjamin Kramer Date: Tue, 21 Dec 2010 21:41:44 +0000 Subject: Add some x86 specific dagcombines for conditional increments. (add Y, (sete X, 0)) -> cmp X, 1; adc 0, Y (add Y, (setne X, 0)) -> cmp X, 1; sbb -1, Y (sub (sete X, 0), Y) -> cmp X, 1; sbb 0, Y (sub (setne X, 0), Y) -> cmp X, 1; adc -1, Y for unsigned foo(unsigned a, unsigned b) { if (a == 0) b++; return b; } we now get: foo: cmpl $1, %edi movl %esi, %eax adcl $0, %eax ret instead of: foo: testl %edi, %edi sete %al movzbl %al, %eax addl %esi, %eax ret llvm-svn: 122364 --- llvm/test/CodeGen/X86/conditional-indecrement.ll | 89 ++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 llvm/test/CodeGen/X86/conditional-indecrement.ll (limited to 'llvm/test') diff --git a/llvm/test/CodeGen/X86/conditional-indecrement.ll b/llvm/test/CodeGen/X86/conditional-indecrement.ll new file mode 100644 index 00000000000..a3a0c39905a --- /dev/null +++ b/llvm/test/CodeGen/X86/conditional-indecrement.ll @@ -0,0 +1,89 @@ +; RUN: llc -march=x86 < %s | FileCheck %s + +define i32 @test1(i32 %a, i32 %b) nounwind readnone { + %not.cmp = icmp ne i32 %a, 0 + %inc = zext i1 %not.cmp to i32 + %retval.0 = add i32 %inc, %b + ret i32 %retval.0 +; CHECK: test1: +; CHECK: cmpl $1 +; CHECK: sbbl $-1 +; CHECK: ret +} + +define i32 @test2(i32 %a, i32 %b) nounwind readnone { + %cmp = icmp eq i32 %a, 0 + %inc = zext i1 %cmp to i32 + %retval.0 = add i32 %inc, %b + ret i32 %retval.0 +; CHECK: test2: +; CHECK: cmpl $1 +; CHECK: adcl $0 +; CHECK: ret +} + +define i32 @test3(i32 %a, i32 %b) nounwind readnone { + %cmp = icmp eq i32 %a, 0 + %inc = zext i1 %cmp to i32 + %retval.0 = add i32 %inc, %b + ret i32 %retval.0 +; CHECK: test3: +; CHECK: cmpl $1 +; CHECK: adcl $0 +; CHECK: ret +} + +define i32 @test4(i32 %a, i32 %b) nounwind readnone { + %not.cmp = icmp ne i32 %a, 0 + %inc = zext i1 %not.cmp to i32 + %retval.0 = add i32 %inc, %b + ret i32 %retval.0 +; CHECK: test4: +; CHECK: cmpl $1 +; CHECK: sbbl $-1 +; CHECK: ret +} + +define i32 @test5(i32 %a, i32 %b) nounwind readnone { + %not.cmp = icmp ne i32 %a, 0 + %inc = zext i1 %not.cmp to i32 + %retval.0 = sub i32 %b, %inc + ret i32 %retval.0 +; CHECK: test5: +; CHECK: cmpl $1 +; CHECK: adcl $-1 +; CHECK: ret +} + +define i32 @test6(i32 %a, i32 %b) nounwind readnone { + %cmp = icmp eq i32 %a, 0 + %inc = zext i1 %cmp to i32 + %retval.0 = sub i32 %b, %inc + ret i32 %retval.0 +; CHECK: test6: +; CHECK: cmpl $1 +; CHECK: sbbl $0 +; CHECK: ret +} + +define i32 @test7(i32 %a, i32 %b) nounwind readnone { + %cmp = icmp eq i32 %a, 0 + %inc = zext i1 %cmp to i32 + %retval.0 = sub i32 %b, %inc + ret i32 %retval.0 +; CHECK: test7: +; CHECK: cmpl $1 +; CHECK: sbbl $0 +; CHECK: ret +} + +define i32 @test8(i32 %a, i32 %b) nounwind readnone { + %not.cmp = icmp ne i32 %a, 0 + %inc = zext i1 %not.cmp to i32 + %retval.0 = sub i32 %b, %inc + ret i32 %retval.0 +; CHECK: test8: +; CHECK: cmpl $1 +; CHECK: adcl $-1 +; CHECK: ret +} -- cgit v1.2.3