From 3d28b1b35be22f445f38d539fa74857b21c1570d Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Tue, 20 May 2008 05:46:13 +0000
Subject: Teach instcombine 4 new xforms:   (add (sext x), cst) --> (sext (add
 x, cst'))   (add (sext x), (sext y)) --> (sext (add int x, y))   (add double
 (sitofp x), fpcst) --> (sitofp (add int x, intcst))   (add double (sitofp x),
 (sitofp y)) --> (sitofp (add int x, y))

This generally reduces conversions.  For example MiBench/telecomm-gsm
gets these simplifications:

HACK2: 	%tmp67.i142.i.i = sext i16 %tmp6.i141.i.i to i32		; <i32> [#uses=1]
	%tmp23.i139.i.i = sext i16 %tmp2.i138.i.i to i32		; <i32> [#uses=1]
	%tmp8.i143.i.i = add i32 %tmp67.i142.i.i, %tmp23.i139.i.i		; <i32> [#uses=3]
HACK2: 	%tmp67.i121.i.i = sext i16 %tmp6.i120.i.i to i32		; <i32> [#uses=1]
	%tmp23.i118.i.i = sext i16 %tmp2.i117.i.i to i32		; <i32> [#uses=1]
	%tmp8.i122.i.i = add i32 %tmp67.i121.i.i, %tmp23.i118.i.i		; <i32> [#uses=3]
HACK2: 	%tmp67.i.i190.i = sext i16 %tmp6.i.i189.i to i32		; <i32> [#uses=1]
	%tmp23.i.i187.i = sext i16 %tmp2.i.i186.i to i32		; <i32> [#uses=1]
	%tmp8.i.i191.i = add i32 %tmp67.i.i190.i, %tmp23.i.i187.i		; <i32> [#uses=3]
HACK2: 	%tmp67.i173.i.i.i = sext i16 %tmp6.i172.i.i.i to i32		; <i32> [#uses=1]
	%tmp23.i170.i.i.i = sext i16 %tmp2.i169.i.i.i to i32		; <i32> [#uses=1]
	%tmp8.i174.i.i.i = add i32 %tmp67.i173.i.i.i, %tmp23.i170.i.i.i		; <i32> [#uses=3]
HACK2: 	%tmp67.i152.i.i.i = sext i16 %tmp6.i151.i.i.i to i32		; <i32> [#uses=1]
	%tmp23.i149.i.i.i = sext i16 %tmp2.i148.i.i.i to i32		; <i32> [#uses=1]
	%tmp8.i153.i.i.i = add i32 %tmp67.i152.i.i.i, %tmp23.i149.i.i.i		; <i32> [#uses=3]
HACK2: 	%tmp67.i.i.i.i = sext i16 %tmp6.i.i.i.i to i32		; <i32> [#uses=1]
	%tmp23.i.i5.i.i = sext i16 %tmp2.i.i.i.i to i32		; <i32> [#uses=1]
	%tmp8.i.i7.i.i = add i32 %tmp67.i.i.i.i, %tmp23.i.i5.i.i		; <i32> [#uses=3]


This also fixes a bug in ComputeNumSignBits handling select and
makes it more aggressive with and/or.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51302 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/Transforms/InstCombine/sitofp.ll | 10 ++++++++++
 1 file changed, 10 insertions(+)

(limited to 'test/Transforms/InstCombine/sitofp.ll')

diff --git a/test/Transforms/InstCombine/sitofp.ll b/test/Transforms/InstCombine/sitofp.ll
index f7b1c91565..73dd23bc43 100644
--- a/test/Transforms/InstCombine/sitofp.ll
+++ b/test/Transforms/InstCombine/sitofp.ll
@@ -31,3 +31,13 @@ define i32 @test5(i32 %A) {
   ret i32 %E
 }
 
+define i32 @test6(i32 %A) {
+	%B = and i32 %A, 7		; <i32> [#uses=1]
+	%C = and i32 %A, 32		; <i32> [#uses=1]
+	%D = sitofp i32 %B to double		; <double> [#uses=1]
+	%E = sitofp i32 %C to double		; <double> [#uses=1]
+	%F = add double %D, %E		; <double> [#uses=1]
+	%G = fptosi double %F to i32		; <i32> [#uses=1]
+	ret i32 %G
+}
+
-- 
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