Combine simplify_set WORD_REGISTER_OPERATIONS

The comment says this test is supposed to prevent "a narrower operation than requested", but it actually only allows a larger subreg not one the same size. Fix that. * combine.c (simplify_set): Correct WORD_REGISTER_OPERATIONS test. From-SVN: r235852

Combine simplify_set WORD_REGISTER_OPERATIONS
The comment says this test is supposed to prevent "a narrower operation than requested", but it actually only allows a larger subreg not one the same size. Fix that. * combine.c (simplify_set): Correct WORD_REGISTER_OPERATIONS test. From-SVN: r235852
343d0287 · Alan Modra · Alan Modra · 475839b6 · 343d0287 · 343d0287
Commit 343d0287 authored May 04, 2016 by Alan Modra Committed by Alan Modra May 04, 2016
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gcc/ChangeLog
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gcc/combine.c
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--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
 2016-05-04  Alan Modra  <amodra@gmail.com>

+	* combine.c (simplify_set): Correct WORD_REGISTER_OPERATIONS test.
+
+2016-05-04  Alan Modra  <amodra@gmail.com>
+
 	PR target/70866
 	* config/rs6000/rs6000.c (rs6000_stack_info): Don't set cr_save_p
 	when cr2,3,4 are all fixed regs.

--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6736,7 +6736,7 @@ simplify_set (rtx x)
 	       + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))
      && (WORD_REGISTER_OPERATIONS
 	  || (GET_MODE_SIZE (GET_MODE (src))
-	      < GET_MODE_SIZE (GET_MODE (SUBREG_REG (src)))))
+	      <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (src)))))
 #ifdef CANNOT_CHANGE_MODE_CLASS
      && ! (REG_P (dest) && REGNO (dest) < FIRST_PSEUDO_REGISTER
 	    && REG_CANNOT_CHANGE_MODE_P (REGNO (dest),